Backpack

A backpack is a common type of bag used for carrying personal belongings, most notably by students at Hogwarts School of Witchcraft and Wizardry to transport their school books, parchment, quills, and other equipment. While most backpacks are mundane, they can be magically enhanced. The most famous example is the small, beaded handbag owned by Hermione Granger, which she enchanted with an Undetectable Extension Charm, turning it into a vital tool for survival during the hunt for Lord Voldemort's Horcruxes.

• Type: Storage; Magical Device (when enchanted)
• Owners: Hogwarts students (mundane versions); Hermione Granger (enchanted handbag)
• Maker: Unknown (for Hermione's handbag); Various (for mundane backpacks)

Standard student backpacks are functional, unremarkable bags large enough to hold textbooks and other school supplies. Harry Potter and Ron Weasley both used such bags throughout their time at Hogwarts. In contrast, Hermione Granger's enchanted container was a small, purple, beaded handbag. Its innocuous and diminutive appearance belied its vast internal capacity, making it an ideal tool for concealing a large number of items without drawing suspicion. The bag itself had no visible straps and was typically clutched in hand.

The primary magical property of Hermione's bag was the Undetectable Extension Charm. This advanced piece of magic vastly increased the internal dimensions of the container without altering its external size, shape, or weight. This allowed an immense quantity of items to be stored inside. Hermione Granger packed the bag in the summer of 1997, demonstrating her characteristic foresight. It effectively served as a mobile base of supplies for the trio during their hunt for Horcruxes. Retrieving specific items often required the user to concentrate on what they needed, though in moments of panic, this could be difficult. Hermione was occasionally seen rummaging through it manually or using a Summoning Charm to find an item. Key contents of the enchanted handbag included:

• Clothing for Harry, Ron, and herself.
• A large number of books, including reference tomes for identifying Horcruxes.
• The portrait of Phineas Nigellus Black.
• Perkins's tent.
• Sleeping bags.
• The Invisibility Cloak.
• Polyjuice Potion.
• Essence of Dittany and other healing potions.
• The locket of Salazar Slytherin after it was stolen from Dolores Umbridge.
• The Tales of Beedle the Bard.
• Food and other provisions.

Mundane backpacks are used by students from their first year at Hogwarts. They are a standard part of a student's equipment, purchased along with other school supplies in Diagon Alley. Hermione Granger prepared her enchanted handbag prior to Bill Weasley and Fleur Delacour's wedding, anticipating a sudden escape. When Death Eaters attacked The Burrow following the fall of the Ministry of Magic, the bag proved indispensable. Hermione carried it for the entirety of their journey, and its contents were the primary reason the trio was able to survive for months while on the run. The bag was confiscated by Snatchers when the trio was captured and taken to Malfoy Manor, but Hermione managed to retrieve it during their escape.

The enchanted handbag is one of the most crucial magical objects in Harry Potter and the Deathly Hallows. It serves as a powerful symbol of Hermione Granger's intelligence, resourcefulness, and unwavering preparedness. While Harry pursued the Deathly Hallows and Ron provided emotional balance, Hermione provided the practical means of survival. The bag is a constant presence during the Horcrux hunt, enabling the trio to travel across the country, set up a secure camp with Perkins's tent, treat serious injuries such as Ron's splinching and Harry's snake bite from Nagini, and carry the Horcrux they had secured. At Malfoy Manor, Bellatrix Lestrange's fear that the Sword of Godric Gryffindor might be inside the bag led her to torture Hermione, a pivotal and harrowing moment in the story.

• The concept of a magical bag with more space inside than outside is a common trope in fantasy fiction, often referred to as a “bag of holding,” famously appearing in tabletop games like Dungeons & Dragons.
• In the film adaptation of Harry Potter and the Deathly Hallows - Part 1, Hermione is frequently shown pulling impossibly large objects, such as books and changes of clothes, from the tiny beaded bag, providing a clear visual representation of the Undetectable Extension Charm's power (film).