Yes, stars are fusion reactors.
No. Our reactors are fission reactors. We haven't yet mastered fusion reactors for power.
Well, fusion bombs are, but fusion reactors should not be (if we can build them).
Nuclear fusion reactors do not exist yet as we don't know how to build them. All nuclear reactors are nuclear fission reactors.
In test reactors.
There are fission and fusion reactors. However, at present (2016) there is no commercial fusion reactor which can produce more energy than is required to operate it.
There are fuel pellets and laser beams inside fusion reactors. But note that we have not build a successful one. The technical problems are overwhelming at this point.
Zero, there are no practical fusion reactors. All existing prototype designs for fusion reactors take far more energy input to make them run than they generate.
allstars
randomly in the jobs and fights
Terry Kammash has written: 'Fusion reactor physics' -- subject(s): Fusion reactors
yes. If they ever perfect hydrogen fusion reactors, then maybe someone will have to come up with a clearer description, but until now, they are the same.
Mostly in test reactors, though some operational reactors (though only a small number) are in service. Also, if you have ever heard of an H-bomb, or a hydrogen bomb, that is nuclear fusion.