From Mandriva Community Wiki
A LiveCD can have more than one goal:
- Demonstration of a Linux distribution
- Operating system installation
- start a mobile operating system, that is to say non-resident
- set of tools ready to use for a given area (system security information, data recovery, multimedia, education, etc..).
How does it works
When the LiveCD is booted, it copies the data necessary for its operation into RAM using a RAM disk for example. A LiveCD does not require the presence of a disk drive, although it can be used as swap if the memory is full. Some LiveCDs require only 32 MB to work with GUI.
A liveCD does not alter the data on the hard disk, although the user can access the hard disk data from the liveCD. The system returns to its previous state when the LiveCD is ejected and the computer is restarted.