According to the limited knowledge that I have, a "stem cell" is an as of yet undifferentiated and unspecialized cell located in a fetus while it's still very very tiny indeed ie; very earliest stages of pregnancy. There's all sorts of special amino acids and hormones and stuff flying around that with a bit of tweaking, can be manipulated into becoming whatever type of cell that is needed. New skin, new nerve tissue, new neurons, new organs etc. Scientists have been messing around with stem cell research in an effort to synthesize the action (I guess) as a part of regenerative medicine.
The downside to all of this is that messing with fetal stem cells invariabley kills the fetus. So, folks that do this sort of thing are doing it on fetuses scheduled to be aborted by the mother.
Without getting into a discussion of abortion, which is a side issue...what do folks think about stem cell research? Is it to Klaus Mengele-esque?
My tentative conclusion at this point, based on my imperfect understanding of the science and my imperfect morals (what is perfect?) is that if the fetus is going to be termed anyway, why not let it die for something potentially wonderful. My mind is open to changing about this...