Ok I know this is a really stupid question but I honestly don't know anything about music. I just picked up a guitar, learned how to read tabs and started pluckin away.

What "key" is standard tuning in? And how do I tell what "Key" my guitar is in? Wtf is a "key" anyways?
that's not a stupid question at all man. check out these lessons and see if it helps. read them in the order that i put the links in. if you have any questions after you read them, post them here.

standard tuinging isn't in any key. It is a tuning that makes it easy to play in a large number of different keys.

A Key refers to which notes are used in a song. The key of C uses A B C D E F AND G. The key of G uses A B C D E F# G. The key of F uses A B C D E F Gb. The Key is useful to songwriters because it helps you to anticipate what chords to use in a not and what notes to use in a melody.
Not taking any online orders.