A kernel that many operating systems called "linux distros" are based off of. Linux is known mainly for being open source, and in most cases, also free to use. Many linux distros are do-it-yourself operating systems, and some come with a full GUI, and many automatic features, which makes it easier for normal people to use. These easy-to-use linux distros are commonly used as a price-effective and useful platform for public and private access to computers, and on servers. Many people criticize this operating system for not being able to run most applications, specifically games. Linux is somewhat limited to which applications it can run, but many people have made alternatives to those applications, and even ways to run those applications inside linux. In fact, many popular games can run on linux, contrary to the packaging of the game. Overall, linux is a great kernel that formed many popular and useful operating systems, which are in use by millions of people today. Linux is also available in a liveCD format, which lets users try linux before they fully install it.