The Standard Book of Spells, Grade 1

“Charms differ from Transfiguring Spells in the following manner: a charm adds certain properties to an object or creature, whereas a transfiguring spell will change it into something utterly different.

“The lesser charms are not very difficult to break and many of those that you learn as a young wizard will wear off in a matter of days or even hours.

“Dark charms are known as jinxes, hexes and curses. This book does not deal with such spells.

“Lapses in concentration while charming can result in painful side effects - remember Wizard Baruffio, who said 's' instead of 'f' and found himself lying on the floor with a buffalo on his chest.

"Some charms will be ineffective against large creatures such as trolls, whose hides repel all but the most powerful spells."