Originally Posted by
JanMM
Yes, you have a freewheel, if you have six cogs.
The vast majority of 6-speeds are freewheels. Shimano did build Uniglide 5-speed and 6-speed cassettes in the late 70's and 80's according to Sheldon Brown. I have worked on my brother-in-law's 6-speed cassette.
http://www.sheldonbrown.com/k7.html