Of course there's Harry and the family who he stays with in the school holidays, the Dursleys - Uncle Vernon, Aunt Petunia and the horrid, spoilt Dudley.
Then there are Harry's mates who he meets at Hogwarts, red-haired Ron Weasley and brainy but brave Hermione Granger.
Hermione's actually based on JK when she was a girl. Let's not forget Harry's main enemies - the ultimate dark wizard, Lord Voldemort, and school bully Draco Malfoy.
And the teachers include headteacher Professor Albus Dumbledore, Professor Snape and Professor McGonagall.