Severus Snape

Character and manners
At the beginning of the story, Snape is presented as a cold, abrupt, withdrawn, and extremely strict man. He often picks on students, especially Gryffindors and Harry Potter in particular, and readily takes their points. His manner is reserved, with plenty of pauses, and his voice is low and ingratiating, sometimes tinged with "steel." He is unsociable, not prone to warmth, and deliberately distances himself from others.
However, as the story unfolds, it becomes clear that this tough exterior conceals deep emotions. Snape has a painful past: during his school years, he was bullied by James Potter and his friends. Another key detail is his unrequited love for Lily Evans (Harry's mother). This bond has largely shaped his actions over the years. In critical moments, he is capable of strong emotions: for example, he wept while clutching Lily's body when she died.
Magical abilities
Snape is a brilliant wizard and master potion-maker. He made significant improvements to the Potions textbook during his student years. He is also the inventor of new spells, such as Sectumsempra. He is also a master of Occlumency (the art of concealing one's thoughts) and Legillimency (the ability to read minds), allowing him to maintain a double identity for extended periods of time, concealing his true intentions even from Voldemort. Snape is a skilled duelist.
Evolution of the image
It's important to remember that in the early books (such as Philosopher's Stone), Harry and the readers perceive Snape almost as an antagonist. His repulsive appearance and cruel treatment of Harry lead them to suspect him of evil intentions. But as the story unfolds (especially in Deathly Hallows), it becomes clear that his actions were driven by complex motivations: love for Lily, guilt, duty to Dumbledore, and a desire to protect Harry.

Hogwarts was founded around the 10th century by four powerful wizards: Godric Gryffindor, Salazar Slytherin, Rowena Ravenclaw, and Penelope Hufflepuff. The school's four houses are named after them. Their goal was to educate and nurture children with magical potential, whom they recruited from across the country.
Description of the castle
Hogwarts occupies an ancient castle located in a secluded mountainous area somewhere in Scotland. J.K. Rowling described it as a vast, haphazardly constructed castle with a tangle of turrets and battlements, held together by magic. Even Headmaster Albus Dumbledore admitted he didn't know all of its secrets.
One of the castle's features is its 142 staircases, which constantly change direction.
How the training is organized
Age and Admission. Hogwarts accepts children aged 11 and over who possess magical ability. Once a child demonstrates talent, their name is entered into the Book of Access, and in July, they receive a letter of acceptance. For Muggle-born wizards, the letter is delivered by a special messenger.
Duration. The course lasts 7 years.
Houses. Students are sorted into four houses: Gryffindor, Ravenclaw, Hufflepuff, and Slytherin. Selection is made using the Sorting Hat, which determines the character traits of the new student.
Exams. At the end of each year, students take exams, but the most important exams are those at the end of 5th and 7th years: the O.W.L.s (Standard Examinations of Wizarding Learning) and the T.A.W.I.D. (Terrifyingly Academically Excellent Assessment).
Subjects. Compulsory subjects include Potions, Transfiguration, Charms, Herbology, Defense Against the Dark Arts, Broomstick Riding, and Astronomy. Electives such as Divination, Care of Magical Creatures, and more are offered starting in third year.

A thin man with unhealthy (sallow, yellowish) skin color.

A hooked nose and long black hair that falls in greasy strands to his shoulders.

Cold, black eyes that are often compared to dark tunnels - there is no warmth in them, unlike Hagrid's eyes.

Thin lips, which are often twisted into a mocking smile.

Yellowish, uneven teeth.

Clothing - a long black robe that flutters as you walk, creating the image of a huge bat