Children (okay, and adults) have been eagerly awaiting today's release of what has come to be known as "the Harry Potter movie." Folks who have been following the series of books about the boy-wizard can appreciate the author's love of language. According to J.K. Rowling, she has relied on old dictionaries and reference books for ideas on how to name her characters.
For example, the name of Headmaster Dumbledore comes from an old dialect term that means "bumblebee," while the name of Rita Skeeter, the pesky reporter for the daily newspaper, even sounds a bit like "a mosquito." It's easy to pick up on the malevolence contained within the last name of Draco Malfoy, but the first name of that mean, young bully also has its nasty side. Draco has an ancestor in the Latin word for "serpent"; back in the Middle Ages, armies would carry a draco, a serpent- or dragon-shaped bag, as a standard as they went into battle.
But for the names Harry Potter and his foe, the evil Lord Voldemort, Rowling didn't have to look beyond her imagination. Harry Potter is the quintessence of a traditional British nickname (remember that there have been eight kings named Henry so far). The adult name of his archenemy, Lord Voldemort, is an anagram of his boyhood name, Tom Marvelo (Riddle).