JKRowling

Rowling was born July 31st, 1965 in Chipping Sodbury, England, and is the daughter of middle class parents. She started writing when she was very young, told stories to her two years younger sister Di, and finished her first written story when she was six.
She attended Exeter University, where she studied French. After collage she worked for Amnesty International researching human rights abuses in French-speaking Africa. It was while she was working in London she thought up the idea for the Harry Potter books. The idea came to her when she was on a train from Manchester to London.
She soon found that she was much more interested in writing than her job and she wrote during her lunch breaks and during meetings. It became obvious that she wasn't really attending to her job and she quit.
When she was 26 years old Rowling went to Portugal to become an English teacher. She worked afternoons and evenings and was able to write during the mornings. While in Portugal she married a journalist and had a daughter in 1993, Jessica, but soon divorced her husband. She returned to England in 1994 settling for Edinburgh, Scotland, with her daughter and "half a suitcase full of papers covered with stories about Harry Potter."
She couldn't afford childcare, so she couldn't go to work and when she tried to get her daughter in state-founded care she was told she was coping too well. For almost a year, until she found teaching work as a French teacher, she lived off public assistance. Thanks to receiving a grant from Scottish Arts Council she was able to finish her book.
Rowling had planned that it would be a seven volume series. "I decided that it would take seven years, from the age of 11 to 17, to train a wizard, and each of the books would deal with a year of Harry's life at Hogwarts". "Harry Potter and the Philosopher's Stone" ("Harry Potter and the Sorcerer's Stone" in the US) was published 1997, followed with "Harry Potter and the Chamber of Secrets" 1998, "Harry Potter and the Prisoner of Azkaban" 1999 and "Harry Potter and the Goblet of Fire" 2000. "Harry Potter and the Order of the Phoenix" (name might change, the 4th book was said to be called "Harry Potter and the Doomspell Tournament" for a long time.) was planned to be published in late July or in November 2001, to match the movie "Harry Potter and the Philosopher's Stone". It has unfortunately been changed to some time in 2002.
By the summer of 2000 Rowling had earned over 400 million dollars for her first three Harry Potter books.

The Harry Potter books are written for children (though I wouldn't say for very young ones), there aren't any particulary hard words, no curses and similar. Still it's written in a way that the books works well with older people too, as it's been proven by the success.
The way Rowling describes people, things and surroundings gives you an idea of what they look like, but it is still not overdone to the point where you can't use your own imagination. That alone makes the books easier to take in and enjoy.

When the books starts Harry Potter is only a year old and it's the day his parents were murdered and he is left at the doorstep of his only living relatives. It later jumps about 10 years forward, when Harry lives with his aunt Petunia, uncle Vernon and cousin Dudley (the Dursleys) who all treat him badly. He is in general a kind and friendly boy, although not always. When he's eleven he finds out how his parents really died (he'd been told that they had died in a car accident until then), that he's a wizard and that he's been accepted to Hogwarts school of Witchcraft and Wizardry.
Harry is thrown into the world of magic, although he is already a big name among the witches and wizards, but he handles it quiet well.
He enjoys school, since he gets away from the Dursleys, although life isn't exactly perfect at Hogwarts either, mainly because of fellow student Draco Malfoy and Professor Snape who both hates him. Facing various dangers (mostly caused by the Dark Lord (Voldemort) who wants him dead to assure his way back to the power he once had) he do what he have to do even though he's afraid.