Magic is an art to entertain people. By the art of magic is not meant that the magicians can really do magic, that is, do what is said, for example, witches. Instead of magic, one also says illusion art: one amazes the spectators by illusions. An illusion is something that only looks like something really is.
The magician makes you believe that he can do something impossible. In reality, however, it is a trick. Some spectators like to be amazed. Other spectators like to guess what tricks the artist is working with.
For centuries, there have been people who have fooled people. Some claimed that they could actually do something that contradicted nature: make things disappear, fly, predict the future. In this way, they wanted to show that a god or a demon was helping them and that they had great power. This was a way to impress people. Other people could supposedly talk to the dead. These frauds did this to get paid by the gullible people.
This was called magic. If the magic was to harm people, it was called black magic or harm magic. Some people were accused of being witches and even condemned and executed. Today, magic is usually just another word for sorcery, and magicians like to call themselves magicians. They say "ma-gi-er."
The so-called magicians of today just want to entertain people: to put on a show that amazes and is fun to watch. This is also called juggling. Since about the years after 1800, there were magicians who did this on big stages and were known in many countries. The most famous magician of all time was probably Harry Houdini. He was particularly good at freeing himself from chains and boxes, even under water.