For this year in school I took up Ap music theroy but I have little or no clue what music theory is because my music teacher never really enforced it. so my question is what is music theroy?

Learning to read sheet music and understanding sounds... or so I believe.

I believe music theory is essentially the elements of music, putting music together and notation. Time signatures, meters, notation, credenzas, ect. are all basic parts of music theory for example. Music theory is also extremely helpful when it comes to composing. Here's something I found that pretty much explains it.

"Music theory is the name for a branch of study that includes many different methods for analyzing, classifying, and composing music and the elements of music. Narrowly it may be defined as the description in words of elements of music, and the interrelationship between the notation of music and performance practice. Broadly, theory may be considered any statement, belief, or conception of music (Boretz, 1995). The academic study of music is called musicology."
en.wikipedia.org/wiki/Music_theory

Not to mention terminology x_x

It really depends. Theory can be the language of music and how it is notated and arranged, or how one note can sound different through various variations, or how or why sounds are created through one medium, and there's more, but 'music theory' is very broad. ;)

http://www.collegeboard.com/student/testing/ap/sub_music.html?musictheory

Music theory is the reason I get up in the morning.

Music theory is the reason I get up in the morning.

Thats funny because Chuck Norris is the reason I get up in the morning.

Music theory is the understanding of how music is set aprt from white noise. And how to do it yourself on an instrument.

I think music theory is just how traditional musicians put together and played music. I think its a bit outdated though.