The tiny details of anything can be called minutiae. Minutia — which you'll usually see as minutiae, the plural version — is a little like trivia.
Notice how minutia almost has the word mini in it? That's a good clue to the meaning, which is "small things or details." People who are sports fans tend to love minutiae — like what a player's batting average is, right down to the third decimal point. Anytime you're dealing with itty-bitty details, you're looking at minutiae.