The_Complete_Idiot%27s_Guide_To_Music_Theory

Introduction
Or, Why You Need to Know a Little Theory
Back when I was in high school and college (a long time ago, and getting longer
every day), many, if not most, of my fellow students regarded music theory as
only slightly more fun than listening to paint dry. I didn’t share that opinion,
and still don’t; I think music theory is interesting and fun and an essential part
of any serious music education.
Still, if all you live for is to play your instrument (or to sing) 24 hours a day, taking
time out from practicing to move a bunch of notes around on paper might
not be tremendously appealing. In fact, I believe introductory-level music theory
classes are the second most-skipped classes in college music schools, with
only music history classes being less well received. (Some enterprising soul is
bound to combine the two classes into a “Theory of Music History”—or “History
of Music Theory”—course, thus creating new levels of student apathy.)
I’m not sure why so many budding musicians are so down on theory. Maybe it’s
because of the way it’s presented. (Let’s face it: Some instructors can be fairly
boring when they present this material, and most music textbooks are stultifyingly
dull.) Maybe it’s because of the way music theory resembles sentence diagramming
and other dreary grammar-related stuff. I don’t know; maybe to
some people, it just seems like a lot of work.
But the fact remains: Every musician needs to know some music theory.
That’s a bold statement, and one that you might take issue with. After all,
you’ve gotten this far in your music studies without knowing theory—why do
you need to start studying theory now?
Or perhaps you know of a famous musician who doesn’t know the least little bit
of music theory—and might not even know how to read music. If this person
became rich and famous without knowing the theory behind the music, why
should you have to learn that theory?
Music Theory Is Important
Famous musicians who don’t know how to read a note of music are the exception
rather than the rule. Most musicians, if they want to communicate with
other musicians—to play in a band, or to teach them their songs—have to know
at least the basics about how music works. These basics—notes, chords, and so
on—are what we call music theory.
Notes and chords are the building blocks of the language of music. Music theory
defines the many different ways you can arrange those blocks into songs
and compositions. Without the theory, all you have is noise; applying music
theory, you can create great works of art.
Musicians apply music theory every time they sit down to play or sing—
whether they know it or not. When you read a piece of music, you’re using