Captain Phasma is a fictional female character who works for First Order in the Star Wars franchise. She has been portrayed on screen by Gwendolene Christie. Captain Phasma is a senior Stormtrooper and the first stormtrooper to be identified as being a female in the films. The fact that she is chrome rather than white is a sign of superiority rather than because the character is female. Its unlikely she was a clone model version but perhaps a conscripted female from one of the many planets that the First Order is in control of. The pictures and the trailer implies that Phasma is an important character and one that is senior and is on the side of the First Order, the successors to the Empire. Phasma will be the first female character that is on the Sith side of the battle although she will not be a Sith warrior. There are females in the Empire but they have only existed in the expanded universe.
You don`t get to see Captain Phasma without her helmet off in the film so it is a little disappointing to to have a "groundbreaking" character and not to actually see her face. She is the commanding officer for Finn who admonishes him for taking off his helmet when Stormtroopers are not allowed to do so. As we didn`t see Phasma without her helmet, it created a bit of discussion and argument on the intenet. A future film should she appear in will probably see her without her helmet.
In an interview, Gwendoline Christies confronted this and responded. She thought it was better to not see the character face and not to judge her on what she looked but to judge her on her actions. ref: EW.
The last we see of Phasma is when she is forced by Finn and Han Solo to drop the shields so that the Rebel Alliance squadron led by Poe Dameron can attack and destroy the Starkiller Base. Her survival is unclear as to her future.Copyright: Lucasfilm