Time Signatures
 

Here's some useful time signature stuff I just scanned:

http://img258.echo.cx/my.php?image=time27mu.jpg

*gasp!*
wrong!:p

Simple time signatures have a bottom number that's either 2 or 4. This top number tells how many beats per bar, and the bottom number tell what note gets the beat. The bottom number is broken up into duple or quadruple.

Compound t/s have a bottom number that's either 8 or 16..etc. This is because instead of telling what note gets the beat, the bottom number is showing the subdivision of the beat. The top number means the same though. The bottom number is broken up into triple.

Something to remember:

if you are in a measure, and you see a triple eighth notes without the "3" above the group, it's compound time.
if you are in a measure, and you see duple eighth notes without the "2" above, you are in a simple time.

the only thing i can never remember is if the time sig comes before or after the key sig

After.