I'm not sure what is the difference between magic and witchcraft... but "سحر" is a general word used for whatever extraordinary practice apart from demonology which is "کهانة" in Arabic. Of course there is also "شعبذة" which is performed by artists as you see in the movie "The Prestige". ok...so far, this is general Arabic language.. but if you want more specific terminologies, then you should also check و کیمیا ، سیمیا، ریمیا، هیمیا، لیمیا، تنجیم، الجفر و الرمل. At this point, سحر has a more specific meaning. As for کرامة, this is what happens by the hands of saints as a gift from God.

In fact in Arabic سحر is more close to witchcraft than to normal magic, because generally in Islam, which is the most influential religion on Arabic language, generally it's not common to believe in someone who says some strange words to do some beyond-nature actions, howerever it's more common to find many people who believe in other people who can use the power of evils to possess people for example or do some specific limited actions against peolple, which is the witchcraft. It's common as well to use this word to express fascination with something, like if it's magic. The other word كرامة is somehow the oppisite of the word سحر, while سحر mainly serves as a bad word about bad behaviors from bad people using bad powers, the word كرامة presents very good people who take an unnatural power from Allah, and that power allows them to do some specific things as a reward for there goodness in this life. I hope it's clear now.

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