Music Class

I am currently taking a music history course as part of my college credit requirements. However, the music history book that was given to me doesn't really explain certain features of music, I guess they assume that I should already know. For example, They talk about the difference between the major and minor scales as being the placement of the half notes. What is a half note? If someone could explain the concept of major and minor scales to me I would greatly appreciate it. Thanks!

Ron

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