Get started with a Raspberry Pi the easy way.  New out of the Box Software or NOOBS is a utility to make installing Operating Systems for the Raspberry Pi simpler for Raspberry Pi beginners but also can be used as a recovery system useful for more advanced users.

Raspbian is a Debian based Linux operating system for the Raspberry Pi. This OS has been developed for the RPi and it's features so is the recommended OS to use.

The RiscOS is a fast operating system designed for ARM processors. Originally owned by Acorn the makers of the BBC Micro used by schools to teach computing in the 80s.

Arch Linux Arm is a Linux operating system designed to be simple and powerful for competent Linux users.