The four Houses at Hogwarts are Gryffindor, Hufflepuff, Ravenclaw, and Slytherin. Each name is worth a look, since Rowling was ingenious here, not only naming each for its respective founder, but choosing names that themselves tell us a lot about the Houses.
Harry’s House is named for Godric Gryffindor. Rowling was supposedly thinking of the element fire for this house. The Sorting Hat tells us in the first book, Harry Potter and the Sorcerer’s Stone (also known as Harry Potter and the Philosopher’s Stone) that
You might belong in Gryffindor,
Where dwell the brave at heart;
Their daring nerve and chivarly,
Sets Gryffindors apart.
The name Gryffindor is closely associated with the mythical griffin, also spelled gryphon and griffon. The griffin has the head and wings of an eagle and the body of a lion. Gryffindor’s animal is a lion, and the house colors are gold and scarlet, lion-like colors. And add in some French to produce griffen d'or, meaning "golden griffen", and you have the name, which apparently is what Rowling did. Interestingly, the name remains the same even in the French translation of Harry Potter, the one which generally has its own names rather than Rowling’s original names.
This House is named for Helga Hufflepuff. Rowling says she was thinking of the element earth for this house, which is odd given the name. The Sorting Hat informs us that
You might belong in Hufflepuff,
Where they are just and loyal;
Those patient Hufflepuffs,
Are true and unafraid of toil.
The name Hufflepuff conjures up images of huffing and puffing. Its resident ghost is the Fat Friar, its head is Professor Sprout (suitably associated with the earth), and its animal, the badger (again, an earthy choice). Interestingly, the French version of the Harry Potter series calls this house Poufsouffle, which in French has very much the same feel as Hufflepuff produces in English.
This house is named for Rowena Ravenclaw. Rowling was thinking of the element air, and gave this house the eagle as its animal. The Sorting Hat describes its member as
Or yet in wise old Ravenclaw,
If you’ve a ready mind
Where those of wit and learning,
Will always find their kind.
The name is an obvious combination of the well-known bird and claw. Its head is Professor Flitwick, and its colors are bronze and blue (or grey in the movies), both easily associated with the sky, flight, and by extension, birds. The French translation uses Serdiagle, which is a nice combination of serrer (meaning to grip or grasp, as in a claw), and aigle, meaning eagle. Other translations keep Ravenclaw in one form or another.
This house is named for Salazar Slytherin. Its symbol is the snake because Salazar Slytherin spoke Parsel, the language of serpents. Rowling views this house as symbolizing the element water. The Sorting Hat says that
Or perhaps in Slytherin,
You’ll make your friends;
Those cunning folk use any means,
To achieve their ends.
The resident ghost is the Bloody Baron, and the head of Slytherin House was Severus Snape, at least until the end of Harry Potter and the Half-Blood Prince. Despite the many Dark Wizards that came out of this house and its history, Rowling herself has defended Slytherin against the impression that it is a bastion of evil. The name has the idea of snakes in it due to the word “slither”, and remains unchanged in the translations of the Harry Potter series except in French, in which it becomes Serpentard, an obvious development.
Hogwarts four Houses are also similar to what exists in many schools in Britain and elsewhere in the world. What makes them particularly distinctive is that students are placed into a particular house by the Sorting Hat during the Sorting Ceremony. The Sorting Hat itself created naming problems in foreign-language editions, with the French choixpeau magique being the most ingenious solution for its fusion of choisir (choose, select) and chapeau (hat).