Deprecation is the discouragement of use of something human-made, such as a linguistic term, a proper name, a feature, design, functionality, piece of code, or practice. Typically a thing previously used is deprecated because it is—or is claimed or thought to be—inferior compared to other options now available. Deprecation is thus a mechanism for future improvement. Deprecation implies that the community (generally, or a community of experts, or a professional body governing a sector or industry) has determined that future use—of the term, name, device, design, or feature—is unwise; but also that its replacement or removal, from that which is extant, is not required or is non-urgent.
Something may be deprecated even though past or extant applications of it might still be useful or functional in particular contexts—the goal here need not be the complete replacement of that which has been deprecated but rather an improvement on some broad metric (eg, safety) of the stock of that thing over time. Thus: deprecation of archaic terms to obtain consistency and readability in language/terminology; deprecation of obsolete electrical components to improve safety and compatibility in the housing stock; or deprecation of certain shared code to improve an open-source software project.[1]
Deprecation typically implies or foreshadows a phasing out, a withdrawal or removal from availability, or a discontinuance of use or support, at some time in the future.