This is a primer for people unfamiliar with Catholicism. It is only a summary. No this is not satire; people actually believe this.
The Pope knows all. The Pope lives in the Vatican in Rome, Italy. The Pope is infallible: whatever he declares to be true, is true, and has always been true. Even if prior Popes declared otherwise.
There is only one God. He created everything.
Jesus Christ is God (and the Son of God), God is God, and the Holy Spirit is God. This is called the mystery of the Trinity.
Humans are inately evil. God was going to send all humans to Hell, a place of eternal torment, but instead allows good Catholics to go to Heaven, the place where God lives. He allows this because Jesus Christ the Son of God died on a cross to redeem our sins. Sins are like negative grocery store coupons. Actually, they are the acts (including thought crimes) that go against various Catholic Church rules. However, once you've got them they are not hard to get rid of.
During Mass, a elaborate ritual prayer session, the Priest turns an ordinary piece of bread, The Host, into the Body of Jesus Christ, and ordinary wine into the Blood of Jesus Christ. Catholics who are without sin (having redeemed their sin-coupons in Penance) can eat the Host and comingle with Jesus.
Priests have to be celibate. They aren't supposed to rape altar boys.
Jesus appointed the Apostle Peter the first Pope, and Peter appointed his successor the second Pope, and so forth, except that now the Cardinals (they're like Bishops, only moreso) select the new Pope. Except God really does it, by answering the Cardinals prayers and telling them how to vote. Except some are hard of hearing, so they vote for the wrong person for a while, until things get cleared up.
Basic sins are: Killing people, hurting people, not obeying authorities like your parents, priests, and the Pope, wanting to have sex, having sex, enjoying sex, stealing, and mocking the Catholic faith. Thinking about sinning is sinning.
The Bible is not the ultimate authority on anything. The Pope is the ultimate authority. If the Pope and Bible disagree, which happens a lot, the Bible is wrong.
Women are yucky. They can't be priests.
Non-Catholics are scum. They should be killed whenever possible. However, if non-Catholics are in a majority and threaten to kill Catholics or discriminate against them, Catholics preach tolerance until they can get back in the drivers seat.
Remember, this is just the basics. Learning everything about Catholicism will take you years of hard work.
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