Hogwarts uniform

The Hogwarts Uniform is a uniform the students wear at Hogwarts School of Witchcraft and Wizardry. Students must wear their uniforms during all lessons, and while eating meals or studying in the Great Hall. Students are allowed to wear their own clothes after lessons in their House Dormitory. Most students are seen still wearing their uniforms in their House Dormitory, most probably because they would need to change into their pyjamas to sleep before they go to bed, so they may feel that it is troublesome to change into their own clothes, than change again into their pyjamas.

Uniform Design
In the books, the Hogwarts uniform consists of a plain black work robe, a plain black pointed hat, and a winter cloak with silver fastenings.

In the films, students wear uniforms consisting of open-fronted black robes with a house insignia on the chest. The part of the black robes that folds towards the hood at the back has the colour of the student's house colour. Red for Gryffindor, green for Slytherin, yellow for Hufflepuff, and blue for Ravenclaw.

Beneath is worn a grey jumper (sweater), white collared shirt, and necktie in the colours of their House. Boys wear long, dark trousers, and girls wear dark pleated skirts and black tights.

Pictures of Uniform Design
Gryffindor Uniform

Slytherin Uniform

Hufflepuff Uniform

Ravenclaw Uniform

Behind the scenes
The design of the Hogwarts uniform used in Harry Potter and the Philosopher's Stone and Harry Potter and the Chamber of Secrets is different from the uniform used in Harry Potter and the Prisoner of Azkaban onwards. The uniform was most probably changed to look more mature, as the characters were getting older.

The pattern of the necktie was changed. The line on the sweater that had the colour of the student's House, was removed from the sweater. The fold on the black robe that folded towards the hood on the back of the robe was also the same colour as the black robe at first, but the colour of the student's house was added to it. The insignia of the student's house that was on the black robe, was still there, but became smaller.

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