BerryBoot is the swiss army knife of Raspberry Pi OS management.

It lets you choose from a range of OSs to boot from a single SD card (if it’s big enough) and lets you move your OS onto an external USB drive. It even downloads the images for you saving you a lot of faffing about with dd or image building utilities.

It’s a great tool for those who like hacking about in different distros but be careful not to wipe a useful SD card!

(Source:  Web Upd8)