The Association of sounds with different height and gravitating to each other, is called a fret. The main sound Lada is the most stable, which tend all the rest, is called the tonic.
Okay, that is a similar Association of the sounds are different. Most common in European music frets, which are called major and minor. At the heart of major tonic triad, in which the first, below, is called a major third (see what is written on the third story "Interval"), and above it a small. Major happens if you came up to the piano, hit consistently all white keys from the notes up to the next note up, placed an octave higher. This continuous sounding of the notes within the octave is called the range. What you played, and - gamma in C major. You can play a major scale from any other sound, only in some places white key to have to replace the black. Because the construction of the schemes subject to certain regularities. So in all major schemes taken after two consecutive tones followed by a semitone, then there are three colors in a row and again semitone, minor scale sounds alternate otherwise: tone, semitone, two tone, semitone, two tone. When gamma is always called by her first sound.