For a laptop/desktop, click on the apple in the upper left, then About this Mac, and it says something like "Mac mini (Late 2012)". Which, if you google it, is

For a laptop/desktop, click on the apple in the upper left, then About this Mac, and it says something like "Mac mini (Late 2012)". Which, if you google it, is actually a model name. You can find repair guides, guides on upgrading, teardowns, etc using that phrase.