A LiveCD is a CD/DVD that is bootable, and it contains an OS and a variety of support software. In this module, Dr. Tak’s LiveCD includes Linux and a variety of tools for general use (such as word processor and web browsing) as well as for software development use (such as assembly language, C, PHP and Perl programming).
As a CD/DVD, the medium containing the OS and programs cannot be overwritten. However, thanks to the COW (copy-on-write) mechanism, changes to the file system stored on the CD/DVD can be saved on a separate file and/or partition.
There are two ways to utilize a LiveCD.
First, a computer can boot with the LiveCD, hence running the Linux environment natively. This approach is more efficient, but it requires the ability to boot from the LiveCD. Computers in the CIS lab cannot boot from a LiveCD due to security and maintenance reasons.
Second, a computer can run a virtual machine, which in return boots from a LiveCD. This approach sacrifices some efficiency due to the virtual machine. However, it gains a great deal of flexibility because this approach can use any computer to run Linux, and it requires a relatively small amount of writeable storage. A single large file can be used for COW purposes, eliminating the need to create additional partitions.