Ready to Upgrade OS

I am currently using Snow Leopard. Did an upgrade from Leopard recently. Plan on doing a clean install to speed up the computer sometime soon.

The latest OS at the moment is Mavericks - free to download from App Store.
However Yosemite (currently being beta tested) will be released in October also as a free download.

Most people like to do a clean install rather than an upgrade. Wipe hard drive and then install new OS. Always make sure you have a working backup (or 2) before installing or upgrading!

The OS after Snow Leopard is Lion (not considered very good by many, but no experience myself) and then Mountain Lion, followed by Mavericks and soon Yosemite. Lion and Mountain Lion cost about $25 to buy.

A consideration - are any of your program running on Rosetta, as Snow Leopard is the last OS to support this. Also what are your current system specifications?
I guess it depends on what your personal needs are.

Hopefully others with more experience will chip in.

Cheers.