Define Folksonomy and SAAS. Do you do this?

Folksonomy is basically tagging and attaching keywords to content posted on the internet, whether a blog post or pictures. Software as a Service (SAAS) is an internet based alternative to traditional software packages. The data remains on a central server, and is accessible from any location with internet service. This is a great tool for those collaborating on a document. I currently do not do folksonomy or utilize SAAS.