COTS, MOTS, GOTS, and NOTS are abbreviations that describe pre-packaged software or (less commonly) hardware purchase alternatives.
- A COTS (commercial off-the-shelf) product is one that is used "as-is." COTS products are designed to be easily installed and to interoperate with existing system components. Almost all software bought by the average computer user fits into the COTS category: operating systems, office product suites, word processing, and e-mail programs are among the myriad examples. One of the major advantages of COTS software, which is mass-produced, is its relatively low cost.
- A MOTS (either modified or modifiable off-the-shelf, or military off-the-shelf, depending on the context) product is typically a COTS product whose source code can be modified. The product may be customized by the purchaser, by the vendor, or by another party to meet the requirements of the customer. In the military context, MOTS refers to an off-the-shelf product that is developed or customized by a commercial vendor to respond to specific military requirements. Because a MOTS product is adapted for a specific purpose, it can be purchased and used immediately. However, since MOTS software specifications are written by external sources, government agencies are sometimes leery of these products, because they fear that future changes to the product will not be in their control.
- A GOTS (government off-the-shelf) product is typically developed by the technical staff of the government agency for which it is created. It is sometimes developed by an external entity, but with funding and specification from the agency. Because agencies can directly control all aspects of GOTS products, these are generally preferred for government purposes.
- A NOTS (NATO off-the-shelf or niche off-the-shelf, depending on the context) product is developed by NC3A (for NATO Consultation, Command, and Control) to meet specific requirements for NATO. In the more general context, niche off-the-shelf refers to vendor-developed software that is for a specialized and narrow market segment, in comparison to the broad market for COTS products.
Unrelated but rhyming is POTS, an acronym for "plain old telephone service."