REST is an architectural style for building web APIs. REST is not a standard per se and is perhaps better defined as a set of constraints (six to be exact) that you should adhere to when defining and/or implementing REST-based APIs.
REST was first introduced by Roy Fielding in his 2000 PhD dissertation titled Architectural Styles and the Design of Network-based Software Architectures at the University of California Irvine.
Although the first (or at least the first publicly known) REST API was launched by eBay in the same year as Fielding's dissertation (refer to https://thehistoryoftheweb.com/ebay-apis-connected-web), the adoption of REST and its main alternative (SOAP/WSDL Web Services) really only gained traction toward the end of 2004 when Flickr first launched its public REST API, shortly followed by Facebook and Twitter.
Of relevance is the fact that while working...