Worf is the first Klingon in Starfleet. He was raised by adoptive human parents -- the Rozhenko family -- after his Klingon father, Mogh, was killed in a Romulan attack on the Klingon colony at Khitomer.
Worf was assigned to the Enterprise-D as a Lieutenant Junior Grade. Upon the death of Natasha Yar, he was given her former position of chief of security. He eventually transferred to Deep Space Nine and has advanced to the rank of Lieutenant Commander.
Worf feels exceptional loyalty to his "Klingon heritage" and has diverted a fair portion of his time in Starfleet to dealing with problems facing the Empire, including the threat of the Duras family and Gowron's inept leadership during the Dominion war.
Worf fathered a son, Alexander Rozhenko, with K'Ehleyr, the half-human/half-Klingon ambassador to the Klingon Empire. Alexander came into Worf's life when K'Ehleyr died. Relations between Worf and Alexander have been strained, and Alexander has been bumped around between staying with Worf and the Rozhenkos.
Late in TNG, Worf began a short-lived romantic interest with Deanna Troi. While on DS9, he married Jadzia Dax, a relationship that ended with Jadzia's death. He tried to maintain the relationship with the Dax symbiont's subsequent host Ezri, but it soon ended.
Worf feels a strong need to "be true to his Klingon heritage" and engages in their masochistic rituals on a regular basis. He does not take kindly to insults, and his favorite human food is prune juice.
While Worf was regularly described as some sort of combat expert, he was often trounced by alien opponents in TNG. Everyone from Lore to a mind-controlled octagenarian to a pack of Ferengi pirates to even a possessed Deanna Troi could get the better of him, causing him to have no credibility in his "bad-ass" role. This is less pronounced on Deep Space Nine.
- K'Ehleyr (mate)
- Nikolai Rozhenko (adoptive brother)
- Alexander Rozhenko (son)
- Sergey and Helena Rozhenko (adoptive parents)
- TNG "Datalore"
- TNG "Conspiracy"
- TNG "The Last Outpost" and TNG "Rascals"
- TNG "Clues"