Twilight Sparkle is an alicorn (and a former unicorn from seasons 1-3), and the main character of the Friendship is magic series. She's a studious mare, a princess, element of magic and former protege to Princess Celestia. She was sent to ponyville in the very first episode of the show by Celestia to check on the preperations for the Summer sun celebration. Here, she learns the importance and magic of friendship, which granted her her ascention to princesshood, granting her her wings and title in season 3. Twilight has always been a keen reader, studying and performing magic spells, and sending friendship reports as her "faithful student" to Princess Celestia. She has a close bond with Spike,a baby dragon she hatched from his egg during her entrance exam into Celestia's school for gifted unicorns, and uses him to send her various letters and scrolls. She also has a pet owl, named Owloiscious.

From the season 4 finale onwards, Twilight is the princess of friendship, who lives in a castle in Ponyville. Here, her 5 friends and Spike stay with her, with their own thrones beside her.

Twilight has been in many forms: Unicorn (From seasons 1-3), Earth pony (Season 2 episode 1), a crystal pony (season 3 episode 2), alicorn (season 3 finale onwards), human (Equestria Girls), and Breezie (season 4 "it aint easy bein' breezie")
Her cutie mark is a pink star with 5 white stars around it.