Well, since we think you're clear on who Harry Potter is—if you're not, we're not sure how you got to this page—we'll focus on that Deathly Hallows part of the title.

As we find out when Hermione reads out "The Tale of the Three Brothers," the Hallows are three objects that, as the legend holds, were gifts from death (distributed originally to three brothers) that can make someone immortal if possessed at the same time. The objects are a wand that can beat all other wands, an invisibility cape, and a "resurrection stone" that brings people back from the dead.

Harry and his pals aren't sure if the Hallows exist (or have the powers detailed in the story), but they know one thing for sure when the movie ends: Voldemort believes in the existence of a super powerful wand, and he's after it.