How do concepts change?

Welcome to the forum, Cindy! That’s a great question. First, I’d say that if you create a variant of a concept, then if it’s still basically the same concept, you shouldn’t invent a new name. It makes it hard for people to understand your app if you have a subscription concept, for example, in which which users can subscribe to notifications about certain events, and you call it “registration.” It’s especially bad if you pick a name that makes it seem like another concept. This is what Twitter did by using the name “favorite” for a concept that was really “upvote” (and led to the amusing mistake a certain former first lady made, a story I tell in my book).

When a concept becomes different enough that it merits a new name is a tricky one. Adobe, Apple and Microsoft have very elaborate style concepts (eg, for paragraph formatting), and they’re different in many small details, but it wouldn’t make sense to use different names—everyone knows what “style” is, and expects it to be slightly different in different contexts. On the other hand, it would be super confusing if Github gave the name “password” to the personal access token concept, just because both of them authenticate by having you enter a string that is matched against a string submitted earlier by the owner of a resource. A big clue here is that the two concepts, although superficially similar, have different purposes.

The case of upvotes/likes/reactions is really interesting because I would argue that Upvote and Reaction are two well defined and independent concepts, but in the design of Facebook they’ve been merged (ie, sync’ed), so that you can’t react without also upvoting.

Of course we don’t yet have a shared catalog of concepts with a consensus on names. My book tries to get that process going, but it will depend on some community consensus.