Nichelle Nichols – American actress and singer who first plays Uhura
Lieutenant Uhura is the communications officer serving on the bridge of the starship Enterprise and Enterprise-A in the original TV Star Trek and the first six Star Trek films.
Uhura is one of the few black women to take a prominent role in 1960’s American television. Previously, black women had been cast as servants or foreign ‘primitives’ in the popular media.
As for the name itself:
“Uhura” comes from the Swahili word uhuru, which means “freedom”. Nichols states in her book Beyond Uhura that the name was inspired by the fact that she had with her a copy of the book Black Uhuru on the day she read for the part.¹
With the inclusion of an international crew, program creator Gene Roddenberry hoped to eradicate racism and many other forms of prejudice. The original series, however, may seem sexist from a contemporary standpoint.
Zoë Saldana – American actress and dancer who plays a younger Uhura
In the 2009 film Star Trek, a younger Uhura is played by actor Zoë Saldana. We learn that she’s a former student of Spock, who is also romantically involved with him. In the sequel, Star Trek Into Darkness, she and Spock are still romantically involved.²
The young Kirk flirted with Uhura at a earlier point in the story arc, but she rebuffed him. However, on board the Enterprise they have a good rapport, and share their frustrations in dealing with Spock (Kirk as best friend, Uhura as his lover).
Uhura is particularly heroic when using her linguistic skills to face hostile Klingons by herself, getting Kirk and Spock out of a jam³ (Klingons had not joined the Federation of Planets at this time in the overall storyline).
² It might seem this film takes too much artistic license by having the super-emotional Spock play the lover. Would not Spock’s emotional repression be worse at a young age, only flowering, perhaps, in old age? This is one way of looking at it. Another is that Spock had not mastered his emotions at a younger age, and he increases mastery as he grows older. In defense of the film, Spock’s father Sarek was married to a human woman, Amanda, so romance must come into play in a Vulcan’s life. This also means that Spock is only half Vulcan. He’s also half human.
³ For more details see http://en.memory-alpha.org/wiki/Nyota_Uhura_%28alternate_reality%29