Objects used by Voldemort to conceal parts of his soul and tether him to life. They can only be created after committing murder
Voldemort's Horcruxes fact file
Objects of great importance to Voldemort, used to conceal parts of his soul
- Magical properties
Once created, the Horcruxes make the wizard immortal as long as they remain intact
- When it was made
The first was made while Voldemort was still at school, his last was created when he murdered Bertha Jorkins
Slughorn sang plaintively: ‘And Odo the hero, they bore him back home...
Harry Potter and the Half Blood Prince
by J.K. Rowling
Well, you split your soul, you see, and hide part of it in an object outside the body. Then, even if one’s body is attacked or destroyed, one cannot die, for part of the soul remains earthbound and undamaged. But, of course, existence in such a form...
The scream of rage, of denial, left him as if it were a stranger’s: he was crazed, frenzied, it could not be true...
Harry Potter and the Deathly Hallows