ELI5: Explain Like I'm 5

User requirements document

A user requirements document is a paper you write to explain to big people what you want in a new toy or game or something. Suppose you want a new toy wheelbarrow or video game, and you tell your parents, they might forget what you said, or not understand it.

A user requirements document is like a long letter that tells everyone who might make your new toy or game everything you want it to have. It lists all the things you need to play with the toy, the features you want in it or the things you want it to do.

It is important to tell the toy makers everything you need and want as it saves you from getting a toy that cannot do everything that you want it to do. The document helps the toy-makers know what the toy should have, and how to make it.

So just like when you tell your parents what you want in your new toy or game, you do the same thing with a user requirements document, but this time it's for grown-ups who will make the new toy or game.