[[center: [-[[Characters/HarryPotter Main Character Index]] | [[Characters/HarryPotterTheTrio The Trio]] | [[Characters/HarryPotterHarryJamesPotter Harry James Potter]] | [[Characters/HarryPotterRonBiliusWeasley Ron Bilius Weasley]] | [[Characters/HarryPotterHermioneJeanGranger Hermione Jean Granger]] | '''Hogwarts Students''' | [[Characters/HarryPotterGryffindor Gryffindor]] |[[Characters/HarryPotterSlytherin Slytherin]] | [[Characters/HarryPotterRavenclaw Ravenclaw]] | [[Characters/HarryPotterHufflepuff Hufflepuff]] | [[Characters/HarryPotterHogwartsTeachers Hogwarts Teachers]] | [[Characters/HarryPotterMinistryOfMagic Ministry of Magic]] | [[Characters/HarryPotterOrderOfThePhoenixMembers Order of the Phoenix Members]] | [[Characters/HarryPotterDeathEaters Death Eaters]] | [[Characters/HarryPotterMuggles Muggles]] | [[Characters/HarryPotterMagicalBeings Magical Beings]] | [[Characters/HarryPotterAnimalsAndPets Animals and Pets]] | [[Characters/HarryPotterOtherCharacters Other Characters]] | [[Characters/FantasticBeasts Fantastic Beasts]] | [[Characters/HarryPotterOtherCanon Other Canon]]]]-]

[[folder:All Houses]]
->''Bold Gryffindor, from wild moor,''
->''Fair Ravenclaw, from glen,''
->''Sweet Hufflepuff, from valley broad,''
->''Shrewd Slytherin, from fen.''

->''They shared a wish, a hope, a dream,''
->''They hatched a daring plan''
->''To educate young sorcerers''
->''Thus Hogwarts School began.''
-->-- '''The Sorting Hat'''
* AnimalMotifs: Each House is represented by an animal:
** Gryffindor has lions, strong, powerful and often associated with bravery.
** Slytherin has snakes, cunning, ambitious and sneaky.
** Ravenclaw has (ironically, given the name) eagles, wise, noble and dignified.
** Hufflepuff has badgers, kind, loyal and diligent.
* ColorCodedForYourConvenience: Each houses also have their own heraldic colors
** Gryffindor: Red and gold
** Slytherin: Green and silver
** Ravenclaw: Blue and bronze (Blue and silver in the films)
** Hufflepuff: Black and yellow
* FatalFlaw: All of them have one:
** Gryffindors have recklessness and their occasional tendency to be glory hounds.
** Slytherins have ambition (a strange example, seeing as that's also the trait they pride themselves in) and occasional elitism.
** Ravenclaws have pride.
** Hufflepuffs have the occasional tendency to be overly kind and forgiving.
* FourElementEnsemble:
** Gryffindor has fire, reflected by its prominent staff member Hagrid, who loves dragons and its common room having a roaring fireplace.
** Slytherin has water, reflected by its head of house Snape, who brews potions and its common room being close to the lake.
** Ravenclaw has air, reflected by its head of house Flitwick, who is first introduced teaching his students to levitate feathers and its common room being in the highest tower.
** Hufflepuff has earth, reflected by its head of house Sprout, who works with magical plants and its common room being underground.
* FourTemperamentEnsemble. The Sorting Hat says it best, but here's a summary: Gryffindor values bravery, daring, nerve, and chivalry. The members can also be short-tempered and reckless so the house is choleric. Hufflepuff values hard work, dedication, patience, loyalty, and fair play. It is the most welcoming house so it is sanguine. Ravenclaw values intelligence, knowledge, and wit. Thus, many Ravenclaws tend to be academically motivated and talented students so the house is phlegmatic. Slytherin house values ambition, cunning and resourcefulness. They believe that some wizarding families are better than others so the house is melancholic.
* LazyDragon: Hogwarts School's CanisLatinicus motto translates as "Don't tickle a sleeping dragon", alluding to the idea of long-slumbering dragons who may turn fierce when woken up but are otherwise safe to be around.

[[Characters/HarryPotterGryffindor See here]]

[[Characters/HarryPotterSlytherin See here]]

[[Characters/HarryPotterRavenclaw See here]]

[[Characters/HarryPotterHufflepuff See here]]

!!Other Groups

[[folder:Dumbledore's Army]]

->''"Every great wizard in history has started out as nothing more than what we are now: students. If they can do it, why not us?"''
-->-- '''Harry Potter'''

Created by Harry, Ron and Hermione as a response to [[SadistTeacher Dolores Umbridge's]] prohibition on teaching students to defend themselves against Voldemort, Dumbledore's Army is the Hogwarts equivalent to the Order of the Phoenix. Its members are Hogwarts students who want to fight Voldemort, and they learn defense from Harry in the Room of Requirement. They communicate using gold coins modified by the Protean Charm to display summons.

Though their activities were interrupted by Dolores Umbridge, Dumbledore's Army remained active in the sixth and seventh books, contributing to the defense of Hogwarts. The organization was named by Ginny Weasley, who said that what the Ministry of Magic would most fear was Dumbledore raising his own army.
%%* BadassCrew
* BecomingTheMask: The name was originally just a joke based on the Ministry's paranoia that Dumbledore was using the class to build his own private army. By the time of the seventh book, they're a real fighting force that fights for Dumbledore's values.
%%* BigDamnHeroes
* BreakingTheFellowship: Umbridge breaks them apart in ''Order of the Phoenix'', leaving plenty of DA members like Neville a lot lonelier come ''Half-Blood Prince''.
* ChildSoldiers: The DA was originally just meant to teach self-defense, but once Hogwarts became the setting for the decisive battle for the Wizarding World, Dumbledore's Army fought alongside real soldiers against the armies of Lord Voldemort.
* CounterfeitCash: Hermione created fake Galleons to be carried around by every member of the DA. The point isn't to spend them like real money, but to give the DA a covert object that can communicate the date of the next DA meeting.
* DeathOfAChild: Quite a few members are killed while attempting to fight the villains-notably, [[spoiler:Colin Creevy, Fred Weasley, and Lavender Brown die.]]
* FisherKing: Dumbledore's Army makes use of the Room of Requirement, which produces books, targets and any materials the DA needs on a whim.
* IWasJustJoking: Their name is originally a joke based on the idea that Umbridge refused to train them in defensive magic because she's "afraid that Dumbledore was putting together a private army." When Umbridge finds out about them, however, she takes the name with deadly earnest -- and, after a while, so do they.
* KidHero: The DA trains students from every year to be ready to fight Voldemort, and quite a few them prove themselves against the Death Eaters.
* LaResistance: Initially against Umbridge, but the DA was always formed with the idea of subverted Voldemort's agenda. Once the second war really kicks into gear, the DA is perhaps the best organized force of resistance against the Death Eaters.
* MildlyMilitary: They may call themselves an Army and actively resist the rule of Voldemort by the seventh book, but they're really just a bunch of teenage students informally acting as teachers and hanging out in an abandoned classroom.
* SchoolClubFront: Dumbledore's Army was formed with this intention (although they weren't keeping its purpose a secret, they weren't exactly openly advertising for members), but Umbridge got wind of it and had a rule allowing her to veto clubs introduced. As a result it became more of a secret club, the only one openly acknowledging Voldemort's return, and [[spoiler:La Résistance in the 7th book.]]
%%* TeethClenchedTeamwork: At first.
* TookALevelInBadass: In the fifth book, they were merely a group of students who wanted to learn Defense Against the Dark Arts. In the seventh, they're a full blown LaResistance group [[spoiler:and most of the members take part in the FinalBattle.]]
%%* TrainingThePeacefulVillagers

[[folder:The Slug Club]]

->''"Horace [Slughorn] formed a kind of club of his favourites with himself at the centre, making introductions, forging useful contacts between members, and always reaping some kind of benefit in return..."''

An informal circle created by Potions master Horace Slughorn to bring together promising young students. Horace selects those who are famous, have famous relatives or have demonstrated exceptional talent, and interviews them. If they pass the interview, then they are invited to parties hosted by Horace, who also invites alumni who were in the club. This way, he can cultivate connections, ensure that club members become important, and be able to call in minor favors from them.

Members include Horace Slughorn (founder), Voldemort, Lucius Malfoy, Lily Evans, Gwenog Jones, Harry Potter, Hermione Granger, Ginny Weasley, Cormac [=McLaggen=], Blaise Zabini, Neville Longbottom (book only), Marcus Belby (film only), and the Carrow twins (film only).
* AmbitionIsEvil: Subverted. The circle is a way for Slughorn to get ahead without directly leading, and getting ahead is the non-bigotry component of the Slytherin credo.
* DancesAndBalls: Slughorn holds a Christmas dance with all the Slug Club and guests in attendance. It seems Slughorn even invited some alumni of the club to it, including a real vampire.
* DarkIsNotEvil: Just because it's an elite circle run by a Slytherin doesn't mean it's bad. Lily Potter, nee Evans, was in it and she is one of the nicest people in the series.
* DoesThisRemindYouOfAnything: For fraternities and "inner circles" such as the Bullingdon Club at Eton or the Skull and Bones.
* InitiationCeremony: Interview with Slughorn, followed by attendance at a party.
* LighterAndSofter: Compared to the other organizations in the series.
* YoungFutureFamousPeople: What Horace hopes the people in his circle will become.