Linux is a Unix-like, open source operating system that was created by Linus Torvalds in 1991. Although it is not as popular in home computers as Windows or MacOS, it is the OS of choice for servers, super computers, main frames, and other pieces of computer hardware like TiVo DVRs. There are many different versions of Linux; some of the more popular ones like Ubuntu and Red Hat are installed onto the computer's hard drive, and some of the others are LiveCDs which do not require a hard drive to operate.
LiveCDs are bootable computer operating systems that are loaded into and run from the random access memory (RAM) instead of from the hard drive. Despite the name, they can also be stored on DVDs, USB drives, or other kinds of transportable media other than a CD. LiveCDs can be useful when you are having trouble with your regular operating system since some of the distributions come with useful tools that can help back up files, scan for viruses, and optimize operating systems. When used for these purposes, they can be considered as Rescue CDs.
The LiveCD distributions reviewed in this website are Puppy Linux (Lucid Puppy) and Trinity Rescue Kit 3.4, Build 372. Click on the links above to see the functions of each distribution.