J.K. Rowling has unveiled four new 'Harry Potter' books.

The author will be releasing a series of non-fiction eBook shorts called 'Harry Potter: A Journey Through...', which is adapted from the audiobook 'Harry Potter: A History of Magic'.

A statement on the Pottermore website reads: ''Prepare to delve deeper into the rich history of magic (be it our own Muggle history, or the magical world created by Jk Rowling) with this new series of eBook shorts. In addition to exploring the origins of magic through history and folklore, the eBook shorts will also feature notes, manuscript pages and charming sketches as previously seen in Harry Potter: A History of Magic.''

The four ebooks are titled 'Harry Potter: A Journey Through Charms and Defence Against the Dark Arts', 'Harry Potter: A Journey Through Potions and Herbology', 'Harry Potter: A Journey Through Divination and Astronomy' and 'Harry Potter: A Journey Through Care of Magical Creatures', which will be published via Pottermore Publishing in the next few months.

The first pair of ebooks - 'Charms and Defence Against the Dark Arts' and 'Potions and Herbology' - will be released on June 27. The second pair is to follow later.

The eBooks will be available in four languages initially - English, French, Italian and German initially, and are available to pre-order at Amazon, Apple and Kobo.

Meanwhile, J.K. Rowling previously admitted that her writing is the biggest part of her life and is more of a ''need than a love''.

Answering what she loves most about the writing life on her website, she said: ''I can't answer this without sounding melodramatic. The truth is that I can't really separate a 'writing life' from 'life.' It's more of a need than a love. I suppose I must spend most of my conscious life in fictional worlds, which some people may find sad, as though there must be something lacking in my external life. There really isn't! I'm a happy person, by and large, with a family I adore and quite a few activities I enjoy. It's just that I have other worlds in my head that I often slip in and out of and I don't really know how it would feel to live any other way.''