An actor is a person who portrays a character in a performance (also an actress; see below). The actor performs "in the flesh" in the traditional medium of the theatre or in modern media such as film, radio, and television. The analogous Greek term is ὑποκριτής (hupokritḗs), literally "one who answers". The actor's interpretation of their role—the art of acting—pertains to the role played, whether based on a real person or fictional character. Interpretation occurs even when the actor is "playing themselves", as in some forms of experimental performance art.
Formerly, in ancient Greece and Rome, the medieval world, and the time of William Shakespeare, only men could become actors, and women's roles were generally played by men or boys. After the English Restoration of 1660, women began to appear on stage in England. In modern times, particularly in pantomime and some operas, women occasionally played the roles of boys or young men.
- Classical acting is a philosophy of acting that integrates the expression of the body, voice, imagination, personalizing, improvisation, external stimuli, and script analysis. It is based on the theories and systems of select classical actors and directors including Konstantin Stanislavski and Michel Saint-Denis.
- In Stanislavski's system, also known as Stanislavski's method, actors draw upon their own feelings and experiences to convey the "truth" of the character they portray. Actors put themselves in the mindset of the character, finding things in common to give a more genuine portrayal of the character.
- Method acting is a range of techniques based on training actors to achieve better characterizations of the characters they play, as formulated by Lee Strasberg. Strasberg's method is based upon the idea that to develop an emotional and cognitive understanding of their roles, actors should use their own experiences to identify personally with their characters. It is based on aspects of Stanislavski's system. Other acting techniques are also based on Stanislavski's ideas, such as those of Stella Adler and Sanford Meisner, but these are not considered "method acting".
- Meisner technique requires the actor to focus totally on the other actor as though he or she is real and they only exist in that moment. This is a method that makes the actors in the scene seem more authentic to the audience. It is based on the principle that acting finds its expression in people's responses to other people and circumstances. It is based on Stanislavski's system.