Hikaru Sulu is a character in the original Star Trek series, played by George Takei. He was originally staff physicist, but ended up being transferred to helm. He gets promoted to captain and gets his own ship in Star Trek VI: The Undiscovered Country. He has one daughter named Demora Sulu who was introduced in Star Trek: Generations.
His ultimate fate has not been documented. It's widely assumed that he retained command of the USS Excelsior after Star Trek VI. In 2350, future Voyager first officer Chakotay was sponsored by Captain Sulu for entrance into Starfleet Academy. Sulu also featured in the Star Trek: Voyager episode "Flashback".
As with many of the minor characters, he is somewhat of an enigma—his first name wasn't even established into Trek canon until that last film (it had been mentioned in novels and the animated series, but neither are considered to be canon). The character is meant to be of pan-Asian decent, but was raised in San Francisco. Hikaru is a Japanese name, while Sulu is taken from a province in the Philippines. In the Japanese version of Star Trek, his name is changed to Kato, at least partly because the Japanese language lacks distinction between L and R. The best reason offered is that Sulu cannot be a Japanese name and if the last name is to be the character's name, the first name would have to be changed to an ambiguous Asian name.