Natasha "Tasha" Yar is a character that mainly appeared in the first season of the American science fiction television series Star Trek: The Next Generation. Portrayed by Denise Crosby, Yar is chief of security aboard the Starfleet starship USS Enterprise-D and carries the rank of lieutenant. The character first appeared in the series' pilot episode, "Encounter at Farpoint". After Crosby decided to leave the series, Yar was killed in the episode "Skin of Evil" near the end of the series' first season. She has a guest appearance in the third season episode "Yesterday's Enterprise", in which her character was still alive in an alternate timeline, and again in the final episode of the series "All Good Things...", which included events set prior to the pilot. Yar was described as a forerunner to other strong women in science fiction, such as Kara Thrace from the 2004 version of Battlestar Galactica, while providing an intermediary step between the depictions of female characters on The Original Series to the command positions they have on Star Trek: Deep Space Nine and Voyager. Some fans have speculated on the sexuality of her character, and that the events in the episode "The Naked Now" were designed to establish her heterosexuality given an otherwise ambiguous portrayal. Source: Wikipedia (en)