Are The Harry Potter Books Aimed At Children Or Adults?

The first Potter books in the series were primarily aimed at children/teenagers, but due to the success of the books, they are now enjoyed by adults worldwide, thus leading to adult versions being published.

The adult editions are exactly the same as the children's edition. The only difference is the front cover of the book. The books were given a new front cover for adults so that they could enjoy the book in public without suffering the embarassment of reading a children's book.

Some of the adult covers consist of photographs based on items from the book. The adult edition of Harry Potter and the Philosopher's Stone has two adult covers, one that has a picture of a train (presumably the Hogwarts' Express) and the other has a picture of a stone (the Philosopher's Stone). Some of the adult covers are illustrated. Goblet of Fire, for example, has an illustration of an oriental dragon.

Aimed at children, but many adults cannot help but muscle in and enjoy them too.
Others like to disparage the books to demonstrate exactly how intelligent, well educated or grown up they are.