Over the years, I've received a number of questions that, effectively, boil down to "what is The Illuminati?", and I hope to answer that question with some certainty here.
The Illuminati is an organization. It is very large, very old, and very powerful. I've taken to explaining it like a mafia. There is, of course, a head of The Illuminati, and a hierarchy of people beneath them. Where a mafia might have some control over a city's police force, politicians, and business, The Illuminati has some control over the world's military and police forces, governments, and various industries such as television, agriculture, et cetera.
The Illuminati is not a satanic organization. It may occasionally use satanic imagery, but that is primarily because that imagery is highly recognizable and often seen as intimidating or frightening. The Illuminati is not associated with any particular religion, although they use religions and their control over religious heads very effectively against the mass populace.
The goal of The Illuminati is a highly contested topic. Some believe they plan to, in essence, take over the world and rule with an iron fist. Some believe they plan to end the world. Some believe they exist simply to guide society into a more appealing future. Personally, I believe the first goal is correct, in that they mean to exert control over the world and establish a new world order in which they have total domination. This is a personal belief and is not verifiable fact at this time.
Not all celebrities are part of The Illuminati, but many celebrities are under their influence and pass on their messages. When in doubt, assume the worst.
While not all politicians are members of The Illuminati, a large percentage of them serve under someone who is. While they may not serve directly under an Illuminati member, if you go high enough up the chain of command, you will almost certainly find one.
Mind control, brainwashing, and other such tactics are almost certainly not employed by The Illuminati. This is one thing I got very, very wrong when I was last around. They cannot control your mind or hypnotize you, at least not through subliminal messaging in media.
I beseech you to ask your questions. If I do not know the answer, I will try to find out.