It's hard to find clear information about this particular religion on the Internet, at least I found it hard. The best thing to do is go to your local library. Good luck! Believe me when I tell you that you don't want to believe everything people tell you about it, because most are wrong.
If you want a first hand answer call 411 and ask for the main church located on Sunset Boulevard in Los Angeles, they will send you all the information immediately. Be careful, they have tried to get many followers to turn in or sell all their personal property and give the money to the church.
It ought to be the 'study of science' but it's not. It's a system of belief that some call a religion and others a cult. Since it's a system and not some simple idea, I can't give you much of a picture of it. Your best bet is to ask in Yahoo religion chat and get a lot of opinions.
Scientology is a system of beliefs, teachings and rituals, originally established as a secular philosophy in 1952 by science-fiction author L. Ron Hubbard, then re characterized by him in 1953 as an "applied religious philosophy."
"Scientology is the "official name Church of Scientology, religion-scientific movement developed in the United States in the 1950s by the author L. Ron Hubbard (1911-86). Its forerunner was Dianetics, a form of psychotherapy originated by Hubbard and later incorporated into Scientology."
It is a religious group, founded by L. Ron Hubbard, a one-time science fiction writer turned religions.
It's mainly based on Hubbard's book, DIANETICS. It purports to explain everything explainable about the human mind based on a set of (as I recall it) six basic things humans focus on, one of which is sex. Read Dianetics, oh, it's got to be thirty something years ago, and was singularly unimpressed--and that was before I knew Hubbard had written science fiction before he wrote Dianetics.
The previous answerer offered you the kipped;Ceou might want to click and read what you find there.