Ok so I Found Out Why They Are Called A.06 and B12.
First lets start with A.06:
"A" is the first letter in the alphabet...following me so far? Good!
So lets say "A" now means the first song on the CD. And then the 06 means of the 6 songs on the CD. So "A" is the first song on the CD (like it is on the alphabet) out of 6 songs. So "A.06" means 1st out of 6 songs on the CD.
"B12" is the 2nd song on the CD like "B" is the second letter in the alphabet. The "12" means of 12 songs on the CD. So "B12" is the 2nd out of 12 songs on the CD.