Memory Question

[Frank Flynn]

I have a 500Mhz Dual G4 with 768Mb of Ram.

Today I launched iTunes and got a message "iTunes could not read your Music
Library because there is not enough free memory".

So I launched "Activity Monitor" and saw that most of my Memory was
"inactive" and that I had very little "free".  Rebooting fixed everything
(maybe logging out and back in or just quitting some stuff would have too).

But here's my question:  What do these things mean - "Wired" (isn't all of
it??),  "Active", "Inactive", "Used" and "Free" (well the last two make
sense).

And how did so much of my memory become inactive?

Thanks,
Frank

-- 
Frank Flynn
Poet, Artist & Mystic