The story opens with the unrestrained celebration of a normally-secretive wizarding world which for years had been terrorised by Lord Voldemort in his decades-long bid for power. The previous night, Voldemort, who had for months sought the hidden Potter family, discovered their refuge and killed Lily and James Potter. However, when he turned his wand against their infant son, Harry, his killing curse rebounded upon him. His soul was ripped from his body, and he was forced into hiding, leaving Harry with a distinctive lightning bolt scar on his forehead, the only physical sign of Voldemort's attack. Harry's mysterious defeat of Voldemort results in him being dubbed "The Boy Who Lived".

The orphaned Harry Potter is subsequently raised by his cruel, non-magical relatives, the Dursleys, in ignorance of his magical heritage. However, as his eleventh birthday approaches, Harry has his first contact with the magical world when he is notified by Hogwarts School of Witchcraft and Wizardry that he is in fact a wizard and has been chosen to attend. Each book chronicles approximately one year in Harry's life at Hogwarts, where he learns to use magic and brew potions. Harry also learns to overcome many magical, social, and emotional obstacles as he struggles through his adolescence and Voldemort's second rise to power.

Universe

The wizarding world in which Harry finds himself is both utterly separate from and yet intimately connected to our own world. Unlike the fantasy worlds of Narnia and Middle-earth, the world of Harry Potter exists alongside ours, and many of its institutions and locations are in towns, such as London, that are recognisable to anyone. It is a fragmented collection of hidden streets, overlooked and ancient pubs, lonely country manors and secluded castles that remain utterly invisible to the non-magical population (known as "Muggles"). Wizard ability is inborn, rather than learned, although one must attend schools such as Hogwarts in order to master and control it. Since one is either born a wizard or not, most wizards are unfamiliar with the Muggle world, which appears odder to them than their world would to us. Despite this, the magical world and its many fantastic elements are depicted very matter-of-factly. One of the principal themes in the novels is the juxtaposition of the magical and the mundane; the characters in the stories live utterly normal lives with utterly normal problems, despite their magical surroundings.

Recurring characters in the Harry Potter series

• Harry Potter: The only child of James and Lily Potter, with whom he shares many distinct characteristics, most notably James' untidy black hair and Lily's green eyes. It is also revealed later that he gets his cheekiness from his mother. He was born on 31 July 1980. He achieved fame at the age of one when Lord Voldemort, the most feared wizard in the world, attacked his home, murdering his parents but failing to kill him, though leaving him with his instantly recognisable lightning-shaped scar. In the attempt, Voldemort was ripped from his body by his own backfiring Killing Curse. Harry's survival was shown later to be a result of his mother's love for him, and the fact that she died to save him. At Hogwarts, Harry has shown himself to be a gifted wizard, excelling both at Defence Against the Dark Arts and Quidditch, along with being recognised as a capable leader within his house, Gryffindor, and the school in general. Despite his best attempts, he has been unable to downplay his fame and his inability to do so has at times been a source of great frustration to him, making him the target of unwanted media attention, rumours, gawking (chiefly at his scar) and the ire of professors and classmates alike. However, despite all external pressures, he remains overall courageous, noble, and high-minded, though at times these qualities have been shown to negatively manifest themselves in what Hermione Granger termed his "saving-people thing". He is best friends with Ron Weasley and Hermione, and his enemies are Lord Voldemort, Severus Snape and Draco Malfoy.

• Ron Weasley: Harry's best friend and the sixth of seven children of the kind and poor Weasley family. The Weasley family are one the best examples of supposed "blood traitors". Ron befriended Harry almost immediately upon meeting him during their first journey on the Hogwarts Express. However, a rift once developed between them, due in part to Ron's frustration at being forced to live in Harry's shadow – no doubt magnified by his position as the youngest son in his large and talented family. This gained praise for being an even-handed portrayal of secondary characters, defying the convention that the Hero must have a best friend and a love interest, but the best friend does not need friends or interests of his own. Despite this, he and Harry have remained close through the years, with Ron being a constant companion through Harry's trials and adventures.

• Hermione Granger: The best friend of Harry and Ron who is generally held to be the top student in Harry's year at Hogwarts. Her high intelligence coupled with her reasoned and logical way of tackling challenges have often been a great asset to Harry and Ron throughout their Hogwarts careers and other adventures, though her sometimes bossy and interfering manner has at times been a source of contention between them. Her status as a Muggle-born, along with her intelligence and studious manner, have on occasion made her a prime target for prejudiced, bullying classmates, e.g. Draco Malfoy. Though very proud of her intelligence, she can be insecure and harbors a great fear of being wrong.

• Lord Voldemort: Evil wizard and chief antagonist of the series bent on securing unmatched power and immortality through the practice of the Dark Arts. After years of slaughter in pursuit of his goals, Voldemort was ripped from his body and forced to flee into hiding after his failed attempt on the life of the young Harry Potter. So feared was he at the height of his prodigious powers that even following his downfall most wizards feared to speak his name, referring to him instead as "You-Know-Who", "He-Who-Must-Not-Be-Named", or "The Dark Lord", the latter of which is used primarily by his followers, the Death Eaters.