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Glossary of Terms

This glossary contains definitions for manufacturing and technical terms used within the xTuple ERP user guide. If a definition below contains unfamiliar terms, please look elsewhere in the glossary for additional information. To see terms used in context, consult the index.

ABC Classification

A method for grouping together items having similar transaction value. Those items having the greatest transaction value are considered class A items, while those having the least transaction value are considered class C items. The acronym ABC stands for activity-based costing.

Absolute Calendar

A type of calendar consisting of fixed time periods with specific dates defining the periods. Distinguished from a relative calendar, whose periods are not fixed but are defined in relation to a point in time. The following example illustrates the kind of fixed time period to be found in an absolute calendar: 01/01/2002 to 03/31/2002.

Accounts Payable

Refers to amounts due to vendors for credit purchases.

Accounts Receivable

Refers to amounts due from customers for credit sales.

Actual Cost

The real-time cost associated with an item, including current material and production charges. The actual cost of an item may fluctuate given changes in the cost for materials, or other costs related to changes in bills of materials or routings. The actual cost provides a current record of charges actually incurred by an item. By comparing the actual cost to the standard cost, managers can determine whether costing and production goals are being met.


An administrator is a person charged with maintaining the correct functioning of an xTuple ERP installation. Sometimes called a systems administrator, an xTuple ERP administrator monitors the software, maintains users, and performs other important technical tasks.


Also known as an item alias, an alias provides a means for cross-referencing internal and external customer item information. For example, a customer may refer to an item by a different item number than you do. To avoid confusion and to simplify item lookups you can create an item alias linking the customer's external item number to your own internal item number. The item alias acts as a substitute or alternate identifier. In this way, items may be located using either internal or external item information. Multiple aliases can be assigned to one item, allowing you to cross-reference an item using many different item numbers.

Alignment Page

A formatted grid template printed from within the System module. Alignment pages are used during the creation of report definitions to ensure reports print correctly on your local or network printer.


A term used to describe the status of inventory quantity. Quantity in an item site is considered allocated if either of the following two conditions exist: 1) The quantity is required by an unissued work order material requirement, or 2) the quantity is required by an unissued sales order line item. Once either requirement is issued, the quantity is no longer considered allocated; instead, the quantity is considered to be relieved.

Allowable Part

Designation given to an item that may be stored in a restricted site location.


Originally an acronym for the American Production and Inventory Control Society, the organization is now known as APICS: The Educational Society for Resource Management.

Application Programming Interface (API)

A set of tools and protocols used by software programmers to enable disparate software applications to communicate with each other.


A naming convention designed to maximize specificity in the naming of site locations. The acronym stands for aisle, rack, bin, location.

Available to Promise

Uncommitted inventory quantity available to support new sales orders or the difference between sales orders already booked and the quantity that operations is planning to produce.

Available QOH

A term used to describe inventory that is available immediately to satisfy work order and sales order demand. Available quantity on hand (QOH) is the same as usable QOH.

Available Qty.

Also known as availability, this term describes inventory that considers future demands and orders. The following formula can be used to define available qty.:

Usable QOH + (future supplies within the time horizon) - (demands within the time horizon).


A computer security measure used in networked settings to verify the identity of users attempting to connect to a system.

Average Cost

A costing approach where cost distribution is based on an average of all costs accumulated.


The automatic deduction from inventory of component item quantities executed at the time production is posted for a work order. In xTuple ERP, backflushing is synonymous with the pull issue method. Issue methods are assigned to component items within a bill of materials.


Refers to sales orders that have either not yet been shipped or have been shipped but are not yet invoiced.


Refers to unshipped line items on a shipped sales order. For example, if a customer orders three line items, but only one of the line items is shipped, the remaining two line items would be on backorder.

Bar Code

An alternating series of vertical bars and white spaces of varying widths used to encode information that can be read by electronic scanners. Bar codes increase efficiency and greatly limit data entry errors. Standard bar code formats supported by xTuple ERP include the following: Code 3of9, Code 3of9 Extended, Code 128, UPC-A, UPC-E, EAN-8, EAN-13.

Batch Manager

A utility within the System module which enables users to manage server-intensive requests, including, for example, database queries, reorder level updates, and large print jobs.

Bill of Lading (BOL)

A document issued by a carrier to a shipper which lists and acknowledges the contents of a shipment to be transported by the carrier. A bill of lading (BOL) specifies terms of delivery and serves as a contract between carrier and shipper.

Bill of Materials (BOM)

A list of component parts and specified quantities required to manufacture an item.


A sequential list of operations required to manufacture an item.

Bill-To Name

The name of the customer to be billed for a sales order. In some cases, the bill-to name on a sales order will differ from the ship-to name on the same order.

Blanket P/O

A term used to describe customer purchase orders which may be used for more than one sales order.


Any open, invoiced, or closed sales order line item. Because bookings represent both active and past customer demand, sales order line items that have been deleted before any activity is registered are not considered bookings.

Breeder Bill of Materials

A bill of materials for a breeder item, showing a list of by-products and any associated co-products.

Breeder Item

A logical item from which co-products and by-products are produced. An example use for a breeder item is the screening of raw gravel to produce different sizes of gravel. The breeder item's bill of materials (BOM) defines the inputs in this case raw gravel and the outputs are defined on its breeder BOM (i.e., small, medium and large gravel). A work order is created for the breeder item, but this item is never stocked or produced; again, it is a logical item. Instead, raw gravel is consumed by the breeder's work order, along with labor, and the resulting quantities of co-products and by-products are recorded.

Buy Card

A list, formerly recorded on a card, showing an historical record of items bought from specified vendors.


An item of value that is produced as a result of operations being performed on a breeder item.

Capacity Buffer

The relative load of a resource compared to the desired lead time of items coming out of that resource. For example, suppose we have a shop with a typical lead time of two weeks that has a milling department heavily loaded. Perhaps we have identified milling as our shop's bottleneck and will use the buffer management system to monitor it. The capacity buffer would be two-weeks worth of load, meaning that the milling department can be loaded with up to two-weeks worth of work before it is considered fully-consumed. The capacity buffer size is entered as Max Days Load by the user when they run the capacity buffer status report. When the Buffer column in the display for milling equals 100 we know it is fully consumed.

Capacity Planning

The process used to determine how much labor, machinery, and other resources will be required to manufacture current products and/or new products in the future.


A transportation company responsible for transporting shipments from one location to another.


Any alphanumeric character both upper and lower case including punctuation marks, white space, and other keyboard symbols.


User-defined definition of an item which may be used to provide additional layers of description to an item. For example, item characteristics might be used to specify season or primary vendor. These constitute static descriptions which are not processed by xTuple ERP, but are useful for informational purposes.

Child Item

A synonym for component item.

Class Code

An inventory control mechanism used for categorizing items regardless of item type. Distinguished from product category, which categorizes sold items only.


The percentage of a sales order's value paid to a sales representative for services rendered.


An item that is required for the production of another item. Components are the items listed on a bill of materials. Also known as component item.

Configured Item

A manufactured item that may have item options added to it.

Control Method

A designation which regulates how an item site handles inventory transactions. Item sites may be controlled by the following methods: regular, lot number, serial number, or none.


An item that is processed at the same time as a breeder item, leading to the production of by-products. Co-products may absorb some of the costs associated with the production of by-products.

Cost Category

A classification applied to item sites which specifies how costs should be distributed to the general ledger whenever inventory is received, moved, consumed, produced, shipped, scrapped, or returned.

Costing Element

A term used to describe a specific type of cost incurred by items. The following costing elements exemplify some of these specific costs: material, labor, overhead. Costing elements may be system-defined or user-defined.

Count Slip

A tool used to contribute inventory count totals to a count tag.

Count Tag

The tool used to spearhead inventory counts. A count tag collects inventory count totals either independently or from affiliated count slips to determine the actual quantity on hand (QOH) for an individual item. When posted, the count tag total replaces the QOH balance displayed in the system.

Credit Memo

An accounting mechanism used to confirm that items have been returned by a customer or that an allowance has been made to a customer. Confirmation results in a debit to the customer's accounts receivable account. Sales order credit memos are used to issue credit for sold inventory. Receivables credit memos are miscellaneous, meaning they are not tied to a specific sales order.

Cumulative Schedules (MPS)

Cumulative schedules allow the forced accumulation of inventory in a discontinuous, or lumpy, demand situation where load leveling or continuous production is desired. With this setting, MPS may release more, but never less, than the quantity dictated in a cumulative MPS schedule.


A purchaser who buys the items and services you sell.

Cycle Count

A cycle count is a periodic issue of a count tag to count inventory quantity within an item site. The frequency of cycle counts is defined at the item site level. Because cycle counts may be conducted frequently, they provide better visibility into inventory levels than annual inventory counts.

Cycle Counter

An employee whose job it is to perform cycle counts.

Cycle Count Tags

The count tags created when a cycle count is performed.

Data Cache

A computer storage area where commonly used information can be stored to facilitate the retrieval and use of that information.

Data Entry

The process of typing information into fields found on xTuple ERP screens.

Data Entry Format

Refers to the combination of keyboard characters supported by xTuple ERP data entry fields. Any data entered into a field must correspond to the format supported by that field. For example, date formats must be entered into date fields. Monetary formats must be entered into monetary fields. Some fields have no format restrictions and allow an unlimited number of alphanumeric characters. Data entry formats may differ from locale to locale.


A collection of electronic information that is organized to allow for the rapid storage and retrieval of information. A digital filing system.

Debit Memo

An accounting mechanism used to debit a customer's accounts receivable accounts. Debit memos are not tied to a specific sales order. They may be used as miscellaneous receivables invoices.


The geographic location where a shipment is received.


An on-screen representation of an xTuple ERP report.


The method in which a return material authorization will be handled.


A DTD is a document type definition. It is the part of the world wide web consortium's standard definition of XML which is used to describe valid XML document formats.


The period of time within which an item is considered valid. An effectivity period is usually defined by effective and expiration dates. Effectivity applies to components in a bill of materials, operations in a routing, and prices on a pricing schedule.


The amount of time a user spends clocked-in to a work order divided by the number of work orders the user is working on at the same time.

Electronic Data Interchange (EDI)

A system for exchanging information electronically between businesses, using the Internet.

Engineering Change Notice (ECN)

Notification given by product engineers signifying that changes have been made to the design or configuration of a manufactured item.

Event Fence

A setting on the Item Site master specifying the period of time, measured in days, within which event notifications related to the item site should be issued. If an event affecting the item site occurs within the event fence, then the system will issue a notification.


Any one of a limited set of possible occurrences precipitated by user activity which xTuple ERP defines as having special importance. For example, an event has occurred if QOH for an item falls below zero, if a work order is created, if a sales order line item is cancelled, etc. An event may trigger an event notification, depending on a user's preference settings. For a complete list of system-defined events, see Appendix A, Additional References.

Event notification

A system-generated alert sent to a user whenever an event the user subscribes to occurs.

Event Manager

A utility within the System module which enables users to view and manage their event notifications.

Execution Day

A setting within an Operation screen associated with either a routing or a work order which defines when the specified operation should begin. For example, if the value "1" is entered in the Execution Day field, the operation will begin on the first day of the manufacturing process. If "2" is entered, the operation will begin on the second day, etc.

Expedite Exception

An indication that an order is late. These late orders need to be acted on or expedited. Examples of late orders would include a work order whose start date is past due or a planned purchase order which has not yet been released.

Expense Category

A classification used for assigning purchasing expenses to specified general ledger accounts. Expense categories are only used for non-inventory items.


The process whereby work order material requirements and work order operations are created for a work order.


Refers to those areas found on xTuple ERP screens where data can be entered. Examples include item number fields, date fields, comment fields, etc.


A process whereby planned orders are solidified in the schedule. When you specify that a planned order is firm, you are indicating that material requirements planning (MRP) should not delete it when running planned replenishment orders unless specifically told to do so.

Firmed Order

A planned order that has been firmed in the schedule. Also known as firm planned order.

Fiscal Year

The accounting year for a company. May or may not coincide with the calendar year.


A process either automatic or manual which carries the ending balance for an accounting period forward through to the current account period.

Free On Board (FOB)

The point at which ownership of goods being shipped transfers from the seller to the buyer. Also the point at which the buyer assumes responsibility for transportation costs and risks.


A mechanism for temporarily locking quantity on hand (QOH) values at item sites to facilitate inventory counting and ensure accurate totals. When an item site is frozen, any inventory transactions entered against that item site including work orders will not affect the QOH for that item site. Because of this, inventory counting can proceed using a fixed baseline total. When the item site is thawed, any post-freeze activity is reconciled, bringing the QOH total to its correct value. The freezing/thawing mechanism is designed to ensure you get accurate inventory counts without having to shut down operations. Term is also applied to accounting periods. When an accounting period is frozen, only users granted the privilege of posting to a frozen period can do so. Once an accounting period is closed it can no longer be posted into.


The contents of a shipment.

General Ledger (GL)

The accounting record which lists all the accounts used by a company.


A sales order control which enables agents to delay the packing or shipping of sales order line items.


The process whereby a work order's material requirements and work order operations are deleted. Only work orders with exploded (E) status can be imploded. Released (R) or in-process (I) work orders cannot be imploded. When a work order is imploded, its status changes to open (O).

Input Mask

A template typically featuring separator characters used to guide users doing data entry. A form of light data validation.

Insufficient Inventory

Inventory is considered insufficient if existing quantity on hand (QOH) will not meet the specified demand; however, replenishment orders do exist in the system—and, once these replenishment orders are received, the demand will be satisfied. Insufficient inventory will have positive availability, distinguishing it from short inventory, whose availability is negative.


Refers to items a company owns and expects to either sell or consume as part of its normal operations.


A printed list of items sold to a customer. Also serves as a bill sent to the customer.

Issue Method

The means by which component items are deducted from inventory for work order processing. The issue method a component item assumes is determined at the bill of materials level. xTuple ERP recognizes three issue methods: pull, push, and mixed.


Any unique product, material, subassembly, or part, whether purchased or manufactured.

Item Controls

A series of specifications applied to an item at the item site level. Examples of item controls include ABC class designation, cycle count frequency, and reorder level limits.

Item Image

An electronic graphics file which may be linked with an item in the Item master. An item image may be a visual representation (i.e., photograph) of an item or any related graphic. xTuple ERP supports the following image file types: .PNG, .XPM, .JPG, or .GIF.

Item Option

An add-on, attribute, or quantity which may be assigned to a configured item.

Item Site

An item site identifies and defines the methods and controls used when maintaining a given item within a given site.

Item Source

A vendor who supplies a given item to a company. Because multiple vendors may supply a single item, a single item may have multiple item sources.

Item Substitute

An item which may be used as a replacement for another item.

Job Item

A manufactured item used specifically for make-to-order scenarios where simplified production is required. The Job Costing option at the item site level is used to distinguish job items from regular manufactured items. Job items cannot be maintained in inventory. And they also have no concept of standard cost or cost variances. All costs for job items are actual. The work orders which create job items can only be created via a sales order. The costs for job work orders are accumulated to WIP, and then transferred directly to cost of sales when the job is shipped. Bill of material and routing items may be assigned to job items; however, they will not roll up to a standard cost for job items.

Keyboard Shortcut

An alternative method for performing computer operations using the keyboard instead of the mouse. An example of a keyboard shortcut would be CTRL + S. Selecting the CTRL key on the keyboard followed by the S key will in many cases perform a SAVE operation. This same operation could be handled by pulling down the FILE menu and selecting SAVE, using the mouse.

Key File

A service-independent encryption seed file, which enables you to read encrypted credit card information.


An item type that automatically explodes bill of material items on to a sales order for shipping.

Label Form

A report definition that prints supported label types.

Labor Rate

The cost charged by a work center per hour for labor. A setup labor rate is charged for preparing a work center to run an operation, and a run labor rate is charged for executing the operation. Routinely performed operations may be assigned a standard labor rate.

Lead Time

An item control which specifies the number of days required to either procure or manufacture an item. For purchased items, lead time refers to days required to procure. For manufactured items, lead time refers to days required to produce. Lead times are specified at the item site level.

List Price

The stated selling price for a sold item. Also known as the catalog price.


A mechanism for defining certain display formats based on linguistic and cultural conventions. For example, the manner in which currency, date, and price formats are displayed is controlled by locale settings. xTuple ERP supports multiple locales.


A physical location within a site for example, a bin, shelf, aisle, etc. Also known as site location.

Lot Number

A unique identifier assigned to a series or batch of items produced at the same time which share the same specifications.

Lower Level

The component level. For example, lower level costs are associated with component items.


An adjective describing a production process in which an item is manufactured after a sales order requests the item. If an item is make-to-order, the Stocked At flag in the Item Site master is turned off. When sales orders are issued for make-to-order items, Purchase requests or work orders will automatically be generated to meet sales order demand.


An adjective describing a production process in which an item is typically manufactured before sales orders for the item are received. If an item is make-to-order, the Stocked At flag in the Item Site master is turned on. When sales orders are issued for make-to-stock items, purchase requests will not be generated.

Man Hour

The labor of one worker for one hour.

Manufactured Item

An item that is made, assembled, or otherwise produced.

Master Production Scheduling (MPS)

The process of planning production to meet the demands of current and forecasted orders.

Master Scheduling

A synonym for master production scheduling.

Material Receipt

An inventory transaction that records the receiving of items into inventory.

Material Requirements Planning (MRP)

A time-phased approach used to calculate the materials required to fulfill the master production schedule (MPS). The MRP calculation is made by exploding the material requirements for current and planned orders, with adjustments made for both existing quantity on hand (QOH) and specified lead times. Where shortages are found or anticipated, replenishment orders are recommended. Also, orders are recommended for rescheduling wherever inventory is found to be insufficient to meet the MPS.


Special keyboard character used to facilitate pattern matching. Sometimes referred to as a wildcard.


A material issue method which declares that a component item is expected to take upon itself the issue method applied to it initially at the time of work order explosion. If the component item is pulled to a work order initially, then the issue method for that item will remain pull in the work order material requirements. If the item is initially pushed to a work order, its issue method will remain push. The mixed issue method allows for flexibility in the building of work order material requirements.

Multiple Location Control (MLC)

A setting defined at the item site level which indicates that item quantities for an item may be maintained in more than a single site location.

Netable QOH

A term used to describe inventory that is allowed to be used for inventory planning purposes (i.e., MRP). All quantities (usable and non-usable) outside of non-netable locations are considered part of netable quantity on hand (QOH).

Netable Location

A term for a location where the inventory is considered netable.

Non-Netable QOH

A term used to describe inventory that is not to be used for inventory planning purposes (i.e., MRP). Only quantities located in non-netable locations are considered part of non-netable quantity on hand (QOH).

Non-Netable Location

A term for a location where the inventory is considered non-netable.

Non-Usable QOH

A term used to describe inventory which is not available for issuing to sales orders or work orders. For example, inventory waiting to be scrapped may be flagged as non-usable.

On Order

A term used to describe the status of inventory quantity. Quantity in an item site is considered on order if either of the following two conditions exist: 1.) the quantity is expected via an unreceived purchase order line item, or 2.) the quantity is expected via an unreceived work order. Once either quantity is received, the quantity is no longer considered on order.


A job, task, or process required for the production of an item. Operations are defined sequentially in a routing. The routing may be modified at the work order stage, where work order operations may be defined. Operations are performed in work centers.


A favorable chance for booking sales revenue.

Order Parameter

A series of specifications applied to an item at the item site level which are used by material requirements planning (MRP) when generating MRP planned replenishment orders. Examples of order parameters include reorder level, order up to level, and lead time.

Order Up To Level (OUT)

Indicates the level of planned availability an item site should be replenished up to when material requirements planning (MRP) is run. In cases where the reorder level for an item site exceeds the order up to (OUT) level, MRP will replenish the item site up to the reorder level. OUT levels are defined on the Item Site master.

Outside Process

An external process or service that is performed by someone (i.e., a vendor) outside your company. An item type. Outside process items are treated by the system in much the same way as purchased items are. For example, outside process items will be handled in the same way as purchased items are when material requirements planning (MRP) is run.


The costs associated with the provision and maintenance of a manufacturing facility. These costs include but are not limited to costs related to building rental, utilities, machinery, supervision, maintenance, etc.


Compressed files which may contain either a.) custom software designed to extend the functionality of xTuple ERP without touching the core xTuple ERP source code or b.) upgrade bundles designed to migrate xTuple ERP databases from one version to the next.

Packing List

A document indicating the items that need to be picked for a sales order.


A definition or limit used to shape a query. See also, order parameter.

Parent Item

A top-level manufactured item. Refers to both root items and also the top-level items in subassemblies. Component items are the children of the parent item.

Partial Shipment

A shipped order having a line item whose full quantity is not included in the shipment. For example, if customer ABC orders 20 units of item XYZ, but only 10 units are shipped, that partial line item quantity (10) would constitute a partial shipment of the ordered item.

Pattern Matching

A method for shaping database queries using regular expressions to improve the precision of results. xTuple ERP supports pattern matching using regular expressions in accordance with the portable operating system interface (POSIX) standard.

Phantom Item

An item type used to classify items that are commonly used together during a manufacturing process.

Pick List

A printed list showing the work order material requirements for a specified work order. A pick list is part of a bill of materials.

Planned Availability

A synonym for availability.

Planned Expense

A projected cost arising from the master production schedule (MPS).

Planned Order

Planned orders are a vehicle used by master production scheduling (MPS) and material requirements planning (MRP) to create soft demands for materials and capacity required to meet the production plan. These planned orders are converted to actual work orders or purchase orders as their lead time approaches.

Planned Revenue

Projected income arising from the master production schedule (MPS).


Those employees of a company responsible for planning, scheduling, or procurement.

Planner Code

A planning mechanism designed to categorize items within designated codes.


An entrance to or exit from a data network.

Portable Operating System Interface (POSIX)

An international standard defining how applications obtain the basic services of an operating system.


An enterprise-class object-oriented relational database management system (ORDBMS). The premiere open source database.

Pricing Schedule

A grouping of sold items indicating the prices assigned for specified quantity breaks. Pricing schedules may be assigned to individual customers or to groups of customers by customer type.


A security measure designed to regulate through authorization the activity of users connected to a computer network or system. Typically, a user is able to perform an action if the privilege to perform that action has been granted to the user. If not granted the privilege, the user will be prevented from performing the action. Sometimes referred to as permission.

Product Category

A classification used to categorize sold items. Distinguished from class code, which categorizes items regardless of item type.


The process whereby subcomponents are converted into manufactured items.

Production Plan

A mechanism used for loading sales forecasts into the system. The master production scheduling (MPS) system accounts for production plans when MPS is run.


A potential customer.


A billing term used to specify that payment is expected on a certain day of the month as in the 15th or the last day of the month.


An inventory issue method in which component items are automatically deducted from inventory at the time of work order explosion. Synonymous with backflushing.


A term used to describe the backflushing of work order operations.

Purchase Order

A written authorization used to formalize purchase transactions with vendors.

Purchase Request

An internal notification used to alert purchasing agents of the need to purchase materials.

Purchased Item

An item that is bought from vendors.


An inventory issue method in which component items must be specifically selected for issuance to a work order.

Quantity on Hand (QOH)

The total of all inventory regardless of status. Quantity on hand (QOH) includes usable, non-usable, netable, and non-netable inventory.


A statement issued to a customer indicating pricing and sales terms for specified quantities of sold items. Often a precursor to a sales order.

Quantity Break

The minimum quantity of an item that must be purchased in order to receive a specified price. Quantity breaks are used in both sales order and purchase order pricing.


A request for information issued to a database.


The business function responsible for the receipt of materials into inventory.

Regular Expression

A combination of characters and metacharacters used in pattern matching to shape database queries. Also known as Regex.

Reject Code

A means for labeling purchased items when and if they are returned to the vendor who supplied them. A reject code explains why an item is being returned.

Relative Calendar

A type of calendar in which periods are defined in relation to a point in time. Examples of points in time that a relative calendar period might be defined in relation to include the following: Current Day or Beginning of Current Month or Beginning of Next Quarter. Relative calendars are considered more flexible than absolute calendars because their periods do not describe static, fixed points in time.


A term used to describe the status of allocated inventory quantity. Allocated quantity is considered relieved if either of the following two conditions exist: 1) quantity allocated to a work order material requirement has been issued, or 2) quantity allocated to a sales order line item has been issued.

Reorder Exception

An indication that an item site's projected availability will drop below the reorder level for the item site—or to zero or below if no reorder level exists. Reorder exceptions are a type of event.

Reorder Level

Specifies when a planned replenishment order should be created for an item site. If planned availability falls below the reorder level, then a replenishment order will be created when material requirements planning (MRP) is run. The quantity of the replenishment order will be enough to restore planned availability back to the reorder level or to the order up to (OUT) level, if the OUT level is greater. Reorder levels are defined on the Item Site master.

Replenishment Order

A planned order issued by material requirements planning (MRP) to resupply an item whose available quantity has fallen below its reorder level at the point when MRP is run.


Printed information showing the results of a query run against a database.


A term used to describe site locations. If a location is restricted, only items specifically assigned to the location may be stored there. If a location is not restricted, it will accept any items from the same site.


An independent, historical snapshot of an entire bill of materials or routing that will be permanently saved.

RMA Hold

A hold status for replacement sales orders that prevents items from being issued to shipping if the receipt of all original goods is required first.

Root Item

An item that is not the child of another other item. A top-level manufactured item, for example.

Rough-Cut Capacity Plan

The plan that results when the master production schedule is converted into specific requirements.


A printed list showing the work order operations for a specified work order.

Run Time

The amount of time required to complete an operation for a manufactured item.

Safety Stock

The quantity of stock for an item you want to keep in inventory to protect against unplanned, unforeseeable trends in your order forecasts.

Sales Order

An order placed by a customer for the purchase of sold items.

Sales Representative

A representative to whom sales orders may be credited and commissions paid.


Inventory that is damaged and cannot be used. Also, work order material that cannot be used during the production of a work order.

Serial Number

A unique number used to identify a particular item.


A computer or process which provides resources and services to other computers connected to the network.

Service Item

An item type used for situations where the cost is variable. Work orders for service items are always linked to sales orders. They are not received into inventory or closed via the manufacturing interface, but rather closed when linked sales order lines are shipped. WIP accumulated for service work will be posted to cost of sales at shipping.

Setup Time

The amount of time required to prepare a work center for the performance of an operation. Setup time is charged only once per operation, regardless of the quantity ordered.


The business function responsible for the outgoing shipment of goods.

Shipping Contents

The inventory contained in the shipping WIP for a given site.

Shipping Zone

A defined geographic region, which can be used to perform sales analysis.

Ship-To Address

An address to which sales order items are shipped. Customers may maintain multiple ship-to addresses.

Ship Via

The means to be used for shipping a sales order.


A term used to describe inventory whose availability is negative.


A physical production or storage facility.

Site Location

A physical location within a site for example, a bin, shelf, aisle, etc. Also known as a location.

Site Zone

A defined section or area within a site. For example, separate site zones might be designated to define areas where orders are selected, picked, and packed.

Sold Item

An item that can be sold to customers.

Sold Ranking

Specifies the order in which item sites will be chosen during sales order and quote creation.


An acronym for secure sockets layer. SSL is a security protocol designed to provide communications privacy for client/server applications like xTuple ERP which communicate over the Internet.

Standard Cost

The cost used for posting general ledger transactions. Standard cost is distinguished from actual cost in the sense that standard cost is fixed, whereas actual cost is subject to fluctuations arising from material or production changes. The two costs may diverge. However, they can be brought back into alignment by posting actual cost to standard. Differences between standard and actual costs can be used by managers to determine whether costing and production goals are being met.

Standard Journal

Used to define reoccurring general ledger (G/L) entries.

Standard Journal Group

Used to define groups of standard journals that are often posted together, such as during period end.

Standard Labor Rate

A labor rate used by work centers for standard, defined job positions.

Standard Operation

A template that describes an operation which may be used in multiple routings.

Stock Buffer

An accumulation of items stored in inventory that act as a hedge against demand where the required service time is shorter than a time buffer for that item would allow. For example: If we have a standard part that takes two weeks to produce, but which we must be able to ship in one day, we would stock that item to ensure the one-day service level. In another case, we may be able to produce the item in a day, but sometimes seasonal load changes result in a production bottleneck where the backlog on a critical resource for that item is greater than a day. The stock buffer allows us to continue shipping the item under those circumstances. It is important to note that due dates are irrelevant for orders with stock buffers. The buffer size is determined by the reorder level at the item site.


A manufactured component item.

Tax Authority

Any entity legally-authorized to collect taxes for example, city, county, state, or federal government agencies.

Tax Code

The rate used when taxes are applied to a transaction. Tax codes may contain one or multiple layers of taxation. For example, a single tax code might include only the rate for state tax; whereas, another tax code might combine both city, county, and state tax rates.

Tax Registration

The registration number used by tax authorities to identify businesses and/or individuals. An employer identification numbers (EIN) is an example of a tax registration number.

Tax Selection

A matrix used to find the tax code to apply to an item given the item's tax type and the tax authority with jurisdiction over the transaction.

Tax Type

A system for classifying goods and services into taxable categories.


Determines payment details for accounts payable and accounts receivable.


The process of unlocking QOH values at item sites that have been frozen for inventory counting purposes. See freeze.

This Level

The parent item level. For example, this level costs are associated with the parent item they refer to.


Indicates the number of units, in the given item's inventory unit of measure (UOM), that can be produced in a minute and also the number of minutes that are required to produce one unit, expressed in the given item's inventory UOM.

Time Buffer

The lead time, measured in working days, of a supply order for an item that is not stocked. By working days we mean the days that the shop is available to work, which may exclude weekends or holidays. For example: If a shop typically has a three-week lead time, but does not work weekends, then the time buffer for that shop would typically be 15 working days. The xTuple ERP constraint management system looks at the start and finish dates of a discrete purchase order or work order, removes non-working days for the order's site, and then calculates the time buffer.

Time Fence

The time fence (also known as the demand fence) is used by the master production scheduling (MPS) system to evaluate when forecasted demand (i.e., from production plans) should be used in place of actual demand (i.e., from sales orders) and vice versa. Measured in days, the demand time fence is the period of time extending from the current day to the number of days into the future as specified in this field. The demand time fence option applies only to those items which currently appear on a released production plan. If demand for these items falls within the demand time fence period, then the forecast will be ignored. If demand falls outside the demand time fence, then the larger of actual or forecasted demand will be used. MPS responds to the demand it locates by creating firm planned orders for the required quantities.


A reference to certain displays and reports which represent data in relation to specified calendar periods.


The row of icons or buttons near the top of the application desktop which activate functions when selected.

Tooling Item

A material resource used in the manufacturing process that is returned upon completion of a work order—for example, a reusable mold, apparatus, fixture, or tool. It may be included on a bill of materials (BOM) for an item, usually specifying a fixed quantity. Tooling items can be purchased, manufactured, or sold. A manufactured tool can have a routing, a BOM, and a work order. As with other material items, tools can be tracked as serialized items. The cost of a tooling item is not included in the overall cost of the parent item where it is used.


Any event involving a change in inventory value or status, and the resulting recording of such events in the general ledger (G/L). xTuple ERP recognizes both inventory transactions and G/L transactions. For a complete list of inventory transaction types, see Appendix A, Additional References.

Transit Site

A special site used by transfer orders used to account for in-transit inventory.


The process of converting quantity of one item into quantity of another item.


A collection of printed documents which accompanies a work order. Traveler documents may include the pick list, routing, or packing list. Also known as a work order traveler or shop traveler.


Describes the quantity on hand (QOH) remaining after allocations have been accounted for, as in:

QOH - Allocated Qty. = Unallocated Qty.

See also: Allocation.

Unit of Measure (UOM)

The standard amount in which quantities of an item are managed (e.g., each, pounds, gallons, etc.). In addition to its inventory unit of measure (UOM), an item may be maintained in multiple other UOMs, including shipping UOM, purchasing UOM, etc.

Usable QOH

A term used to describe inventory that is available immediately to satisfy work order and sales order demand. Usable quantity on hand (QOH) is the same as available QOH.

Usage Statistics

Records indicating inventory transaction activity.

User Preferences

Controls found within the System module which users can manipulate to customize their interaction with xTuple ERP. For example, users may customize the appearance of their application desktop or specify the events they are subscribed to.


A software tool designed to perform a specific function.


A formatting requirement used to strictly enforce data entry rules. If you specify a validator for a field, then users will have to conform to the format when entering data. Any data which does not conform will not be accepted.


The difference between an expected result and an actual result.

Vendor Ranking

Specifies the order in which item sources will be chosen during purchase order creation.


A supplier of purchased items.


A document authorizing payment to vendors who have either performed services or supplied goods. A voucher vouches for the fact that these goods or services have been provided.


An acronym for work in process. Refers to inventory in various stages of completion ranging from work order material requirements in production to packaged inventory awaiting shipment.

Work Center

A collection of machines or labor that performs a specific task when building a manufactured item. Work centers are used by the routing to determine the amount of available and required manufacturing capacity to produce the manufactured item. Work centers also determine per-minute run and setup time costs. A single site may contain multiple work centers.

Work Order

A document which demands the production of manufactured items.

Work Order Material Requirement

Indicates the quantity of a given component item that is required to complete the parent work order. A material requirement is derived by multiplying the work order quantity times the specifications set forth in the parent item's bill of materials (BOM). The BOM specifications may be altered at the work order level to fulfill the requirements of a particular work order.

Work Order Operation

Indicates the amount of run and setup time at a given work center that is required to complete the parent work order. An operation is derived by multiplying the work order quantity times the specifications set forth in the parent item's routing. The routing specifications may be altered at the work order level to fulfill the requirements of a particular work order.


An XML transformation language designed by the World Wide Web consortium as part of the extensible stylesheet language. This is supported by xTuple as a mechanism for importing data from XML files into the database. Files containing XSLT are often called stylesheets.


A defined geographic region or specific site area. See shipping zone or site zone.