Warning! Spoiler alert! If you've not read all the books or seen all the movies, don't read!

Harry goes to Hogwarts and becomes friends with Ron and Hermione. They figure out there's a bad guy at school. They go to stop him. Turns out it's Voldemort, the guy who tried to kill Harry when he was a baby. Harry saves the day and the year ends happily.

Harry goes to Hogwarts. Scary stuff happens, and it looks like Voldemort's back. Harry gets help from friends. He and Ron have an adventure. Harry saves the day. The year ends happily.

Harry goes to Hogwarts. Scary stuff happens, and the enemy turns out to be Harry's godfather, who actually is a goody guy. Harry and Hermione do some time travelling. The year ends happily.

Harry goes to the Quidditch world cup. Scary stuff happens, and at Hogwarts, the Triwzard Tournament ropes him in. Funny that. Some more scary and life-endangering stuff happens. Voldemort comes back, Harry's friend is murdered and the year ends tragically.

Harry is almost expelled from Hogwarts. There's a new teacher at school, a toad wearing pink outfits with a love for torture. Nasty stuff happens, Harry and students rebel. They get caught, they escape, they go to the Department of Mysteries and battle Death Eaters. Voldemort shows up. Dumbledore shows up. Minister of Magic shows up. Voldemort vanishes. The year ends somewhat happily.

Harry goes to Hogwarts. He stalks Draco. Draco tries to kill Dumbledore, unsuccessfully. Ron, Hermione and himself experience love. Dumbledore dies, killed by Snape, what? Harry resolves to finish his mentor's quest. The year ends sadly.

Harry leaves his relation's house. Scary stuff happens. He, Ron and Hermione attend a wedding which goes wrong. They live at Grimmauld place until they decide to go undercover in the Ministry of Magic. They get the locket Horcrux. Ron leaves. Hermione cries. They go to Godric's Hollow and almost die. Ron returns, kills locket. They are caught. Hermione is tortured, they escape and Dobby dies. Very sad. They go undercover in Gringotts and steal a horcrux cup and a dragon. They go to Hogsmeade. They get into Hogwarts. Students cheer. Everybody fights so Harry can find the last horcrux. Ron and Hermione kill the cup in the Chamber of Secrets. There's a kiss, finally. Harry learns stuff from a dying Snape. He looks at his memories and knows what he has to do. Voldemort kills Harry. Sort of. Harry's alive after meeting Dumbledore and realizing he was the last horcrux. Harry and Voldemort duel. Voldemort is killed by his own spell because Harry was the true master of the elder wand. Lots of people died. Very sad. Harry and Ginny get married, have kids. Ron and Hermione get married, have kids. They go to Hogwarts, life goes on. The story ends happily.