Slightly stupid question. Freewheel vs Cassette

Are freewheel and a cassette the same thing?

not really…

nowdays you have a cassette and a freehub (which included the ratchet part)

you used to have a freewheel (which consisted of the cogs and the ratchet part) and the hub which it would get threaded on to.

so is a freeewheel compatable with todays cassettes? Can it be converted?

so is a freeewheel compatable with todays cassettes? Can it be converted?
No. The freewheel contains the bearings/pawls that are now found on freehub bodies (Campy or Shimano) attached to hubs. Cassettes are only the cogs, and fit onto the splined freehub bodies. Freewheels screwed onto hubs.

so is a freeewheel compatable with todays cassettes? Can it be converted?
No. The freewheel contains the bearings/pawls that are now found on freehub bodies (Campy or Shimano) attached to hubs. Cassettes are only the cogs, and fit onto the splined freehub bodies. Freewheels screwed onto hubs.
But can the whole axel be pulled out and swapped?

Hello,
The axle can(usually) be pulled out for maintenance on the bearings, but not to convert between an old style freewhee to a newstyle freehub. Typically people ask because they can get a great deal on an older used freewheel type disk. If you are running a six, seven or eight speed rear you can usually find a compatible freewheel to make it work, burt if you have 9 or 10 speed equipment you are out of luck. As a sidenote you used to be able to send a freewheel type zipp disk back and have them redo it for a fee to a modern cassettte system, but I’m not sure if they still do that.

Styrrell