*Jennifer Jane Parker McFly is the girlfriend, and later the wife, of Marty McFly. Jennifer was the world's fourth time traveler, the first female one and the third human one. She was the daughter of Danny Parker Jr. and Betty Parker, and the granddaughter of Danny Parker and his wife Betty Lapinski.

Jennifer and Marty seemed to be "serious" enough for him to introduce her to his best friend, local inventor Dr. Emmett Brown, whom she first regarded as eccentric and strange. Jennifer is mostly a positive person, knowing what to say to Marty if he needed cheering up, and wondering what happy life she might have in the future.

Jennifer was born in 1967 in Hill Valley, California. She was Marty's girlfriend, having met him at Hill Valley High School, which they both attended in 1985.

Sometime before 1985, Jennifer met Marty and started dating him, eventually falling passionately in love with him. She also became friends with Emmett "Doc" Brown.*