Short answers, pulled from the story.
The word character emerged from the Ancient Greek term χαρακτήρ, which originally described a stamp or impression. Dryden used this English sense in 1679 when discussing the chief character of a tragedy.
Before the shift to modern usage, writers relied on the Latin phrase dramatis personae to describe masks worn by actors. This older concept emphasized the literal physical aspect of theatrical performance rather than internal psychology.
E.M. Forster defined two basic types of characters in his book Aspects of the Novel. Flat characters remain relatively uncomplicated and two-dimensional throughout a story while round characters are complex figures possessing many different characteristics that may surprise readers.
Aristotle argued for the primacy of plot over character in classical tragedy theory. He stated that without action a tragedy cannot exist yet it may exist without characters according to his writings.
By the end of the eighteenth century, the phrase in character began describing effective impersonation by an actor. Since the nineteenth century, the art of creating these figures has been called characterization.