cooked disc images

[Underheaven]

I've recently learned that e.g. Safedisc emulation can also be of use for cooked Safedisc CD images
... and as like can RMPS emulation for images of RMPS copies

I was wondering what "cooked" means and how one could accidentaly or intentionally rip a disc to end up with these kind of sectors?

[Terramex]

It means that an CD image only contains the 2048 bytes user data per sector.