Hogwarts Houses

The Hogwarts School of Witchcraft and Wizardry is divided into four houses, each bearing the last name of its founder: Godric Gryffindor, Helga Hufflepuff, Rowena Ravenclaw and Salazar Slytherin.

House system
Houses at Hogwarts are the living and learning communities for its students. Each year a group of a certain house shares the same Dormitory and classes. The houses compete throughout the school year, by earning and losing points for various activities, The house with the most points wins the House Cup. Each house also has its own Quidditch team that competes for the Quidditch Cup. These two competitions breed rivalries between the houses, the greatest of which is that between Gryffindor and Slytherin.

Sorting
In the early days of Hogwarts, the four founders handpicked students for their Houses. When the founders worried how students would be selected after their deaths, Godric Gryffindor took his hat off and each "put some cells" in it, allowing the Sorting Hat to choose students. Now, at the beginning of each school year, the magical Sorting Hat is placed on each new student's head during the Sorting ceremony. The Sorting Hat announces the house the student is to join. Before beginning the Sorting ceremony, it sings a short song about the founding of the school and the four Houses; the Sorting Hat's songs are different every year, and the Hat is said to take all year composing the next one (according to Ron Weasley, at least).

Qualities
"It is our choices, Harry, that show us who we truly are, far more than our abilities."

- Albus Dumbledore

It seems that the Sorting Hat tends to place students based on qualities they value rather than qualities they exhibit. This is never more apparent than with Peter Pettigrew, who was Sorted into Gryffindor but ultimately turned out to be quite cowardly, self-serving and corruptible. He was probably placed there because at the time, he admired strong, brave individuals like James Potter and Sirius Black.

The Sorting Hat can detect nascent qualities in a student and place them in the House that will challenge them and put their character to the test. Case in point, Neville Longbottom was Sorted into Gryffindor because the Hat sensed that he was capable of demonstrating bravery and leadership during his time at Hogwarts. However, these qualities did not fully surface until Neville learned to believe in himself.

The Hat also appears to take the student's wishes into account, considering how one's personal choices are very much of a reflection of the qualities that they values in themselves. Just because someone is placed in a certain House doesn't mean that they can't display characteristics of other Houses. Harry Potter, for instance, embodied many of the traits that were appreciated by Salazar Slytherin. He was clever, resourceful and cunning, yet the Sorting Hat made him a Gryffindor because the very fact that he asked not to be in Slytherin showed that he didn't belong there. A true Slytherin wouldn't have had any doubts about whether or not it was the right House for them.

One of the biggest examples of this was Severus Snape. At one point, Albus Dumbledore observed that his loyal, courageous nature was much more befitted to Gryffindor. However, as a child, Snape's sadism, disdain for Muggles and sheer ambition made him an obvious Slytherin when he first came to Hogwarts.

House dynamics
The four houses are rather separate entities. Each has its own Common Room and Dormitory, its own table in the Great Hall, and students mostly share lessons with classmates of their same house. There is no rule against students from different houses mingling, but in practise, a good majority of social interactions occur within the same house. Each house has one teacher who acts as its Head of House. Each house also has a House Ghost. The function they serve (if any) is unknown, although they might be like house Mascots. Each Head of House and house ghost was previously a pupil within that house.

A great deal of rivalry exists between the houses, not always friendly. This rivalry is demonstrated in the Quidditch matches and the annual school competition for the House Cup, which is determined by the number of points earned or lost by each member of the rival houses. These points are awarded or taken based on students' conduct throughout the school year. All members of the faculty and the Head Boy and Girl have the authority to grant and deduct points as they see fit in each instance. Some, like Severus Snape, the former Potions master, tend to favour their own house, but that does not seem to be against the rules. He is despised by many students, other than those in Slytherin, where he is very popular. It is not known how much favouritism the Hufflepuff and Ravenclaw Heads show, although it can be deduced that it's minimal or non-existent, as both Professor Filius Flitwick (of Ravenclaw) and Professor Pomona Sprout (Hufflepuff) are kind, lighthearted people, who obviously want to win the House and Quidditch Cups but are not as vindictive as Snape in going about it. It is known that Professor Minerva McGonagall, the stern head of Gryffindor, does not show much favouritism towards her house. In fact, she deducted 50 points apiece and awarded detentions to three students in her house (Harry Potter, Hermione Granger, and Neville Longbottom when they were caught out of bed after hours in Harry's first year), and supported Professor Snape wholeheartedly in giving Harry detentions for the rest of the school year, even on overlapping Quidditch matches, after Harry used the Sectumsempra spell on Draco Malfoy in Harry's sixth year.

According to Rubeus Hagrid, "There isn't a wizard that's gone bad that wasn't in Slytherin," (though this is for the most part correct, there are a few exceptions, former Gryffindor Peter Pettigrew the most notable of them). None of this necessarily means, however, that all Slytherins are evil (Horace Slughorn for example). Slytherins are chosen for their cunning and Pure-blood heritage (although Blood purity does not appear to be essential - Lord Voldemort and Snape were Half-bloods, though they both are prejudiced). It has also been said that all four houses must band together and fight as one if Hogwarts is to stand. It must be remembered that all of the Houses have their virtues and flaws: none are inherently good or evil. Slytherins may have earned their reputation as evil because they show such contempt towards Gryffindor, the protagonist house. They also do not show much generosity towards other houses either, whether those in them are pure-blood or not.

House rivalry is most seen between Slytherin and Gryffindor ("Gryffindor and Slytherin students loathed each other on principle"). This rivalry likely goes back to the days of Godric Gryffindor and Salazar Slytherin after they founded Hogwarts, because the Sorting Hat said that they were the best of friends before they founded the school. While it is not clear if there is a similar rivalry between Ravenclaw and Hufflepuff, it seems very much unlikely due to the cheerful disposition of the Heads for said Houses, as opposed to the contempt of Professor Snape and the passion of Professor McGonagall (Rowena Ravenclaw and Helga Hufflepuff, however, once great friends, are documented as having had a severe falling out at some point by the Sorting Hat's song in 1996. However, Ravenclaw and Hufflepuff house members seem to get along just fine, as shown with Cho Chang and Cedric Digggory, who were dating. Also, if the two were rivals it would be more obvious, however the two houses seem to be friendly.

Usually, though not always, the other two houses appear (in Harry's eyes) to support Gryffindor in its rivalry with Slytherin, which again is reminiscent of how Slytherin was in the end opposed by all three of the other Founders. One exception to this occurred when Ravenclaw, Hufflepuff, and Slytherin all initially supported Hufflepuff's Cedric Diggory instead of Gryffindor's Harry Potter in the Triwizard Tournament. Also in the first Quidditch match of 1996, it is said that many of the Hufflepuffs and Ravenclaws had "taken sides" in the Gryffindor vs Slytherin match, but does not specify which Houses took which side.

Gryffindor
Gryffindor values bravery, daring, nerve, and chivalry. Its emblematic animal is the lion and its colours are scarlet and gold. Minerva McGonagall is the most recent Head of Gryffindor. Sir Nicholas de Mimsy-Porpington aka Nearly Headless Nick is the house ghost. The founder of the house is Godric Gryffindor. Gryffindor corresponds to the element of Fire. The common room is located in one of the highest towers at Hogwarts, the entrance is situated on the seventh floor in the east wing of the castle and is guarded by a portrait of The Fat Lady. She permits entrance if given the correct password which is changed numerous times throughout the school year.

Hufflepuff
Hufflepuff, founded by Helga Hufflepuff, values hard work, patience, loyalty, and fair play rather than a particular aptitude in its members. Its emblematic animal is the badger, and Black and Yellow are its colours. Pomona Sprout was the Head of Hufflepuff during 1991 - 1998, Sprout left the post of Head of Hufflepuff and Herbology Professor sometime before 2017 and her successor for the position of Head of Hufflepuff is currently unknown. The Fat Friar is its ghost. Hufflepuff corresponds roughly to the element of earth. The Hufflepuff Dormitories and common room are located somewhere in the basement, near the castle's kitchens. It can be accessed through a barrel with a secret way to get it open and is described as being a cosy and welcoming place with yellow hangings, fat armchairs, and underground tunnels that lead to the dormitories, which have perfectly round doors, similar to barrel tops.

Ravenclaw
Ravenclaw values intelligence, knowledge, and wit. Its emblematic animal is the eagle, and its colours are blue and bronze. The Ravenclaw Head of House in the 1990s was Filius Flitwick. The ghost of Ravenclaw is the Grey Lady, who was the daughter of Rowena Ravenclaw, the house's founder. Ravenclaw corresponds roughly to the element of air. The Ravenclaw common room and dormitories are located in a tower on the west side of the castle. Ravenclaw students must answer a riddle as opposed to giving a password to enter their dormitories.

Slytherin
Slytherin house values ambition, cunning and resourcefulness and was founded by Salazar Slytherin. Its emblematic animal is the serpent, and its colours are emerald green and silver. Professor Horace Slughorn was the Head of Slytherin during the 1997–1998 school year, replacing Severus Snape, who as well, replaced Slughorn when he retired for the first time several years ago. The Bloody Baron is the house ghost. Slytherin corresponds roughly to the element of water. The Slytherin Dormitories and common room are reached through a bare stone wall in the Dungeons. The Slytherin common room lies beneath the Black Lake. It is a long, low underground room with rough stone walls and silver lamps hanging from the ceiling.

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
 * Harry Potter and the Chamber of Secrets (film)
 * 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 Prisoner of Azkaban (video game)
 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Goblet of Fire (film)
 * 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 (film)
 * 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
 * Harry Potter and the Deathly Hallows: Part 1
 * Harry Potter and the Deathly Hallows: Part 1 (video game)
 * Harry Potter and the Deathly Hallows: Part 2
 * Harry Potter and the Deathly Hallows: Part 2 (video game)
 * LEGO Harry Potter: Years 1-4
 * LEGO Harry Potter: Years 5-7

Trivia

 * Each House represent one of the four classical elements: Fire (Gryffindor), Earth (Hufflepuff), Air (Ravenclaw), and Water (Slytherin).