What is an ISO???

[Wanksta]

hey every1,

im fairly new to all of this , and i was just wondering, could someone tell me what an ISO is??what its used for??or whatever, and also what programs i might need to convert the file to an ISO or to burn the ISO to a CD. I have clonyxxl,cd-mate,alchohol,and clone cd.

thanks,

Wanksta