This document provides an overview and installation instructions for the Linux operating system. It discusses that Linux is an open-source, independent operating system with commands similar to Unix. It was introduced by Linus Torvald in 1991-1994. The document also summarizes different Linux distributions like Ubuntu, RedHat, and Mint and covers basic Linux concepts such as shells, users, directories, and case sensitivity. Furthermore, it provides step-by-step instructions for downloading and installing the Ubuntu desktop version on a system with minimum requirements of 1GB RAM, 5GB disk space, and a 1GHz processor.