A Charm is an object that preserves the Magyk of a spell. It can take any form, typically a piece of parchment of something symbolic to the spell, and has the incantation written on it. However, charms have been known to take forms of food, such as toast, as the charms must be made immediately to contain maximum power, and because wizards are notoriously forgetful. If a charm is in a different form than when the spell was written on it (bent, broken, separated, eaten, etc.), the Magyk is lost and the charm is useless.
Charms are typically kept by beginners for spells that they want to do, however, this is not necessary. Keeping a charm will make it easier to recite the spell when using it, as the incantation for a spell is written on the charm. While some spells are easy to remember during practice, it is more difficult to remember every word while in a crisis.
Most charms are kept in Magyk books. The charms are stored in pockets formed by folding the page of the book back on itself. Typically Magyk books will have the instructions for the spell on them. A Magyk book with all of its charms in it is rare.
For a charm to be used, a spell must be Imprinted. To Imprint a spell, the user must hold the charm close to them and recite the incantation, making sure not to miss any words. While doing this, the user must imagine the spell occurring. To remember the words and imagine the spell happening at the same time is difficult.
Some powerful wizards are able to perform spells without speaking, as demonstrated by Septimus Heap on his first attempts to perform his Disappear and when Marcia Overstrand gave him the wings of the Flyte Charm.