Fire-Making Spell

"But Snape parried the curse, knocking Harry backward off his feet before he could complete it; Harry rolled over and scrambled back up again as the huge Death Eater behind him yelled, "Incendio!" Harry heard an explosive bang and a dancing orange light spilled over all of them: Hagrid's house was on fire."

- Hagrid's hut being set on fire

Incendio is the incantation of a spell that conjures fire.

Known practitioners

 * Albus Dumbledore (possibly)
 * Arthur Weasley
 * Bellatrix Lestrange (possibly)
 * Colin Creevey
 * Filius Flitwick (possibly)
 * Fred Weasley
 * George Weasley
 * Harry Potter
 * Hermione Granger
 * Neville Longbottom
 * Pomona Sprout
 * Remus Lupin (possibly)
 * Ron Weasley
 * Rubeus Hagrid (possibly)
 * Thorfinn Rowle

Etymology

 * In Latin, "incendo" means "I set fire".
 * "Incendio" is the Spanish and Italian word for "fire" (as in "forest fire" or "grassfire") or "conflagration".
 * "Incendio" (pronounced in-cen-DI-u) is also the first person singular of the present of the spanish and portuguese verb "incendiar", meaning "to set fire to".

Behind the scenes

 * This may be the spell Remus Lupin used on the Hogwarts Express 1993, combined with a Flame-Freezing Charm when the lights went out as he is described as "holding a handful of flames" though it is more likely that he used the charm for Bluebell flames . This may also be the spell he used to relight candles during the Patronus lesson.
 * In the video game adaptations of Philosopher's Stone and Chamber of Secrets, Incendio is the Bluebell flames charm Hermione uses in the first book. It is used primarily to wilt dank-loving, threatening plants and burn through spiderwebs. In the later games it resumes its use as a spell to conjure a small burst of normal fire.
 * When Rowle used the spell offensively against Hagrid's hut, it caused an explosion, rather than simply lighting it on fire.
 * Incendio is the first known spell to be cast in the series, although magical devices (Albus's Put-Outer), abilities (Animagi) and beings (Hagrid) appeared before.

Appearances

 * Harry Potter and the Philosopher's Stone
 * Harry Potter and the Philosopher's Stone (film)
 * Harry Potter and the Philosopher's Stone (video game)
 * Harry Potter and the Chamber of Secrets (video game)
 * Harry Potter and the Prisoner of Azkaban
 * Harry Potter and the Prisoner of Azkaban (film)
 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Goblet of Fire (video game)
 * Harry Potter and the Order of the Phoenix
 * Harry Potter and the Order of the Phoenix (video game)
 * Harry Potter and the Half-Blood Prince
 * Harry Potter and the Half-Blood Prince (film) 
 * Harry Potter and the Half-Blood Prince (video game)
 * Harry Potter and the Deathly Hallows: Part 1
 * Lego Harry Potter: Years 1-4
 * Harry Potter: Spells

Notes and references
Incendio אינסנדיו Sytyjo