another IPOD (touch) question

[Villavic]

Hi
when I open the Itunes, with my itouch connected, all of my music, 2000 songs, appear at Devices\ipod device name\MUSIC. A friend of mine told me to do so, instead of copying to the library cause he said is faster.

But when I want to du a backup of my songs, the option mentions the LIBRARY, and at Library\MUSIC there are just few songs. I don't find to move my songs to Library\MUSIC, and I don't find the way to backup songs from Devices\ipod device name\MUSIC (this last is what I actually want, what should I do?)