J.K. Rowling launched Pottermore in 2011 as an interactive website for the Harry Potter world.
Pottermore opened to the public in 2012 after an earlier limited registration period. It offered interactive experiences based on the Harry Potter books, including sorting into a Hogwarts house, wand selection and additional writing by Rowling.
The site also became a digital retail platform for Harry Potter e-books and audiobooks. Rowling used it to publish background information and stories that expanded details about characters, locations and wizarding history beyond the main novels.
Pottermore was renamed Wizarding World Digital in 2019, and the broader consumer brand became known as Wizarding World. That later name can cause confusion when identifying the original website. The answer is Pottermore because that was the name used at its 2011 launch.