The Philosopher's (Sorcerer's) Stone.
Lord Voldemort shared a body with Professor Quirrell.
Professor Quirrell was sharing a body with Lord Voldemort.
It was called the Philosopher's Stone. In some editions this is known as the Sorcerer's Stone.
Lord Voldemort is correct. His real name is Tom Marvolo Riddle. I Am Lord Voldemort is an anagram of Tom Marvolo Riddle.
Snape doesn't want or need to get the Philosophers Stone, he is one of the staff protecting it Professor Quirrell wants the stone for his master (Lord Voldemort) He is sharing his body with Lord Voldemort.
Tom Marvolo Riddle."I am Lord Voldemort" is an anagram of "Tom Marvolo Riddle", which is Voldemort's name at birth.
Lord Voldemort's real name is Tom Marvolo Riddle. Marvolo is the name of his maternal grandfather.
Lord Voldemort did want to kill Harry. He promised that he wouldn't because Harry had the philosopher's stone and Voldemort wasn't powerful enough to take it off him, but Voldemort was unlikely to actually keep that promise even if Harry had joined his side and handed the stone over.The only reason Voldemort didn't try to kill Harry is because he had no body, he was sharing Quirrell's but had no actual control over him.
Lord Voldemort in the Philosopher's Stone was the real, current Voldemort/Riddle. In the Chamber of Secrets, the young Tom Riddle is actually an imprint of his soul in the diary, and not actually, physically him, but a past version of himself. Since the diary is a horcrux, the Riddle in the diary is PART of Voldemort, but not actually Voldemort.
None of the professors were Lord Voldemort. Quirinus Quirrell, the Defence Against the Dark Arts Professor, was sharing his soul with Voldemort and had his face on the back of his head.
Harry prevented Lord Voldemort from gaining the Philosopher's Stone and returning to power. Voldemort was very weak and was forced to go into hiding, where he remained until 1994 when he was found by Peter Pettigrew.
Lord Voldemort. Because of the terror he spread in the past, most wizards and witches - with the notable exception of Albus Dumbledore, and Harry Potter - are afraid to pronounce his name.