Comment by pbmonster

The temperatures are far beyond anything matter can stand, so its very important that the magnetic confinement keeps the plasma from touching anything.

But one end product of the fusion process is neutrons. Neutrons are unaffected by the magnetic confinement, they pass right through and hit the jacket of the reactor, where they are absorbed. This heats up the material, which is why you can run cooling water through the jacket which turns into steam. This steam spins a turbine.

There's some engineering challenges (neutron bombardment turns steel and concrete brittle, and later radioactive), but in the end its very similar to a normal fission reactor.