An end-item is a system, equipment, or an assembled article ready for its intended use. Only ammunition or fuel or other energy source is required to place it in an operating state.

A component is an item that is useful only when used in conjunction with an end-item. A major component includes any assembled element that forms a portion of an end-item without which the end-item is inoperable. A minor component includes any assembled element of a major component.

Accessories and attachments are associated articles for any component, equipment, system, or end-item, and which are not necessary for its operation, but which enhance its usefulness or effectiveness.

A part is any single unassembled element of a major or a minor component, accessory, or attachment which is not normally subject to disassembly without the destruction or the impairment of designed use.

Firmware and any related unique support tools (such as computers, linkers, editors, test case generators, diagnostic checkers, library of functions, and system test diagnostics) directly related to equipment or systems covered under any category of the U.S. Munitions List are considered as part of the end-item or component. Firmware includes but is not limited to circuits into which software has been programmed.

Software includes but is not limited to the system functional design, logic flow, algorithms, application programs, operating systems, and support software for design, implementation, test, operation, diagnosis and repair. A person who intends to export only software should, unless it is specifically enumerated in § 121.1 of this subchapter (e.g., USML Category XIII(b)), apply for a technical data license pursuant to part 125 of this subchapter.

A system is a combination of parts, components, accessories, attachments, firmware, software, equipment, or end-items that operate together to perform a function.

Note to paragraph (g): The industrial standards established by INCOSE and NASA provide examples for when commodities and software operate together to perform a function as a system. References to these standards are included in this note to provide examples for when commodities or software operate together to perform a function as a system. See the INCOSE standards for what constitutes a system at: http://g2sebok.incose.org/app/mss/asset.cfm?ID=INCOSE%20G2SEBOK%202.00&ST=F, and in INCOSE SE Handbook v3.1 2007; ISO/IEC 15288:2008. See the NASA standards for examples of what constitutes a system in NASA SE Handbook SP-2007-6105 Rev 1.

Equipment is a combination of parts, components, accessories, attachments, firmware, or software that operate together to perform a function of, as, or for an end-item or system. Equipment may be a subset of an end-item based on the characteristics of the equipment. Equipment that meets the definition of an end-item is an end-item. Equipment that does not meet the definition of an end-item is a component, accessory, attachment, firmware, or software.