Jack is a half-brother to Shawn Hunter
- Jack appeared in Brothers and spoke to Shawn and Chet. It was the first time that they had spoken in many years.
- Soon thereafter, became the roommate of Eric and Shawn.
- Warned Shawn to stop drinking when Elaine left their father, because he was an abusive drunk and that alcoholism runs strongly in their father's side of the family.
- Kicked Shawn out at the beginning of season 6, and began competing with Eric for Rachel's affections.
- Began dating Rachel in Road Trip, following his father's death.
- Broke up with Rachel in State of the Unions.
- Was kicked out of his apartment in season 7, and began a frantic search for a place to live with Eric.
- Graduated from Pennbrook & joined the Peace Corps with Rachel.
- Jack can speak Chinese.
- Is somewhat smart, but for some reason Eric gets the better of him and occasionally he gets involved in Eric's antics.
- Formerly known as "Jumbo Jack", until he started working out to bring his body fat count down to 6%.
- Jack is a Mac user (Season 7 Episode 16, Seven the Hard Way).
- Jack loves ice skating, which is one of the few things that he and Shawn have in common.
- In The Witches of Pennbrook Jack reveals he's from New York City.