I am learning Redux (a JavaScript state container tool). I am finding numerous references to something called a "selector" (e.g. here, here, here, and here). However, I don't seem to be finding a simple definition of what a selector is (as opposed to, say, examples of selectors or details about some aspect of selector function which, while helpful, don't answer my main question). Stack Exchange and general Google searches don't seem to help (contaminated with lots of hits for CSS selectors which clearly are fundamentally different). So, in the context of Redux, what exactly is a selector? And is it a concept that is specific to Redux or is it a more general term? A link to official or unofficial documentation somewhere would also be helpful.
1 Answer
From Laiv's comment and What are selectors in redux? a Redux selector is
a function that knows how to extract a specific piece of data from the store.
SELECT.