Charm

A type of magic spell concerned with enchanting an object to behave in a way that isn't normal for that object. For example, the Summoning Charm brings an object to the caster. Charms is also something of a catch-all for spells that aren't Transfiguration (spells that change the inherent nature of an object). In some sense, if a spell isn't Transfiguration, it's probably a Charm.

A Charms spell might cause something to flash different colors. It might cause an object to levitate or even fly through the air. Charms can make a person laugh or dance or even create a bubble of breathable air around a person's head.

Some Charms can be extremely powerful. The Fidelius Charm, for example, can completely hide a person or a place in such a way that no one can find them unless they are given the location by a Secret Keeper. Memory Charms can be so strong that they completely remove a person's memory or even damage their mind permanently.

Charm spells are in some ways the opposite of Curses: many Charms seem to have in inherent positive tone (e.g. Tickling Charm) while Curses have an inherent negative one. This is not to say that Charms are weaker magic; a well-chosen Charm is a powerful magical tool against Curses, Jinxes, and Hexes. Professor Flitwick, the Hogwarts Charms teacher, was rumored to have once been a duelling champion, after all