I studied a little about Satanism in school and then forgot much of what I learned. I was reminded by a few nice ladies here when I had questions not too long ago.
Satanism is the worship of self and the bettering of ones self. You are your own god and you make your own rules and moral code based on what bennefits you and those you care about. Common sense is involved in forming ones own moral code because performing an action that has a negative consequence is not benneficial. Negative consequences vs. the bennefit of the desired action are weighed out. Satan is viewed as a concept, rather than a literal, existing being. The concept of Satan is defiance of God/gods, defiance of non-free-thinking and the defiance of obeying a higher power. Some Satanist also believe in manipulating magic forces and some witchcraft.
Some people that use the title "Satanist" do actually worship Satan as a diety.
at 4:55 PM on Jun. 23, 2009