"Or perhaps in Slytherin
You'll make your real friends,
Those cunning folks use any means
To achieve their ends." ~ from Harry Potter and the Sorcerer's Stone
Slytherin house is one of the four Houses of Hogwarts School of Witchcraft & Wizardry. Established by Salazar Slytherin, those students chosen by the sorting hat for this particular house are chosen due to their purity of blood, and their cunning and ambition. Students in this house can be ruthless, cunning, and the house itself is often associated with the dark arts. If a student is accepted to this house as a mere half blood, or even worse, a Muggle born, they would do best to remain silent on the matter, lest they face a horrible upcoming seven years.
Slytherin house's animal is the snake, its green and silver, and its current head of house is Finella Croyden. The patron ghost of this house still remains as the Bloody Baron.