Articles

[intro:]       the introduction section of a song
[verse:]       verse section
[verse: instrumental]  a verse section where it is only (mostly) instrumental
[solo: ]       a solo section, indicates which main instrument performs the solo
[chorus:]      chorus section - subsequent chorus section(s) may change during the song
[bridge:]      bridge- subsequent bridge section(s) may change during the song
[pre-chorus:]  a section which introduces the chorus - subsequent pre-chorus section(s) may change during the song
[coda:]        the end section of the song
[:]            a segment where is does not quite fit into any of the above
{ }            comments and/or instructions 
|              beginning or end of a bar. Example,  |  | imdicates one bar.
Am/F           Am chord with F bass note
( lyrics )     sung by background vocals. Example, (oooos-aaaaahs)

(G)           a passing note, a note to provide a smooth transition from one chord to another. For example,
              a guitar player may play a G major between an Em to Am progression. Likewise, a bass player may play a 
              between the Em to Am progression. 
arpaggio      a chord in which individual notes are played one by one rather than all together at once