Lord Voldemort, initially called Tom Marvolo Riddle, was an evil, dark wizard. Tom was once a student of Hogwarts School of Witchcraft and Wizardry. A student of Slytherin House, Tom was an exceptionally brilliant young wizard, showing prodigious skill in his work and an uncanny sense of emotional intelligence. Tom however came from a lowly background. While his father was a wizard, his mother was a poor muggle (non-witch) who birthed him in poverty. All of this was arbitrary and his misfortunes were not purposefully determined. Tom always nursed a disdain for his piteous origins and focused his brilliance on creating a superior new identity for himself, later living to become the most vile, dark wizard the wizarding world had ever known. He fashioned for himself a new name- Lord Voldemort, alternatively known as the Dark Lord, and built a cult of dark wizards known as ‘Death Eaters’ who did his bidding.
Voldemort later found out that his life was tied to Harry Potter’s, and that he had to kill Harry if he was to survive. In his bid to achieve this, he resorted to the most horrifying things, even killing those he considered third party casualties. In essence, Lord Voldemort was the epitome of all that was vile, dark and undesirable to the wizarding world.