Key Signature ID (Major keys)
There are three main accidentals used in standard notation: the sharp, the flat, and the natural.
At the beginning of each piece of music, you will often find a key signature. Generally speaking, a key signature tells the reader which notes are always made flat or sharp. In the key of C, no sharps or flats are necessary to produce the characteristic sound of the scale, "Do-re-mi-fa-sol-la-ti-do".
However, when you begin the scale on a different pitch, it is necessary to alter the pitches to fit the pattern. Key signatures make reading music simpler by indicating to the reader the position of DO.
Memorize the key signatures by practicing the exercises below. It will take some practice, but these are arranged in an order that will help you do it.
* Also, see the attached Circle of Fifths PDF for details.
* Click here for a tutorial.