[mcdowall]

I'd classify it into three groups for the UK...

Perm - Mid level benefits + Pay (maybe options in a startup)

Contractor - Individual with their own Ltd company, pays less tax and much higher take home pay but without any benefits.

Consultant - On-site via a supplier on a framework of some kind, however, often a permanent employee of the supplier with the supplier cashing in the margin.

At least 50% of the tech workforce in companies I work with or where peers are at in London are made up of contractors, especially in Banking.