The only half decent answer so far... Some more points that seem important.

Judaism, Christianity and Islam are all monotheistic religions. That means they insist people worship only one god - in fact, they deny the existence of any others (though this wasn't always the case for Judaism).

Islam, Christianity and Buddhism are "universal" religions - believers believe that the religion is for everyone, and that they have a duty to spread the religion. This is not the case for Judaism.

Jews follows a (complex) set of laws and rules (although how strictly they follow them varies a lot). Muslims follow five key rules, like charity and regular prayer, though they have some of the same taboos as Jews, like not eating pork. Christians don't place this same emphasis on specific rules or even on behaviour. Generally what's most important is belief - belief in God and in Jesus as saviour.

If you do or believe the right things, when you die your soul will go to heaven (though you might have to go through purgatory first).

Buddhists believe that the world we perceive is an illusion and that the goal of life is to free ourselves from this illusion - what they call "enlightenment". They believe souls are reincarnated over and over until they become free.

Buddhists generally believe in a range of gods, demigods and mystical beings, who can help or hinder people on earth or in achieving enlightenment. Buddhism is very "syncretic" meaning it mixes easily with other religions, like Hinduism, Taoism and Shintoism.