Unix / UNIX is a multitasking, multi-user computer operating system. Unix was originally developed in 1969 by a group of AT&T employees at Bell Labs, but since then there have emerged many different "breeds" of Unix operating systems, most of which are free and open source. While the popular breeds differ in their graphical user interfaces, what all these operating system have in common is that they are built with the same backend and "Unix shell". From this page I have collected some of my own notes on different Unix commands, shell scripting and other topics. For better information about Unix itself you'll see a link to the wikipedia page down the bottom!