In each of them we can learn more about the history of Hogwarts and Harry Potter universe. The series is called "Pottermore Presents".
"Pottermore Presents is a series of electronic booklets that delve into the stories of Harry Potter, with fragments taken from the archives of Pottermore and original writings of JK Rowling."
The beautiful covers of this series were designed by Miraphora Mina and Eduardo Lima.
In "Hogwarts: An Incomplete and Unreliable Guide" find from details about the ghosts of the beloved school to what is what happens when the Sorting Hat can not assign a home.
"Short Stories from Hogwarts of Power, Political and Pesky Poltergeists" tells about the darker side of the magical world from problems in the Ministry of Magic to the horrors of Azkaban.
Finally, in "Short Stories from Hogwarts of Heroism, Hardship and Dangerous Hobbies" know more details about the most beloved teachers of Hogwarts.
The books are available in English, French, German, Italian, Japanese, Dutch, Brazilian Portuguese and Spanish. Can you buy them at Pottermore , Amazon, iBooks, Barnes & Noble and more.