Harry Potter series, written by J.K. Rowling, have attained enormous fame and commercial success over the world. This series tell a story about a young wizard, Harry Potter, and his adventures with his friends, Hermione and Ron to fight the evil. The books received both positive acclaim and strong criticism. But anyway, this work is still the most successful one of J. K. Rowling and turn her into a billionaire. The Harry Potter series has had an enormous impact on society. There are fewer children who arrive at the emergency room on days, symposiums are held to discuss the books, and strange magical words that are used by the wizards in the book are introduced into the Oxford English Dictionary, for examples.