From Wikipedia: Sophocles (c. 497/496 – winter 406/405 BC) was an ancient Greek tragedian, known as one of three from whom at least one play has survived in full. His first plays were written later than, or contemporary with, those of Aeschylus; and earlier than, or contemporary with, those of Euripides. Sophocles wrote over 120 plays, but only seven have survived in a complete form: Ajax, Antigone, Women of Trachis, Oedipus Rex, Electra, Philoctetes, and Oedipus at Colonus. For almost fifty years, Sophocles was the most celebrated playwright in the dramatic competitions of the city-state of Athens which took place during the religious festivals of the Lenaea and the Dionysia. He competed in thirty competitions, won twenty-four, and was never judged lower than second place. Aeschylus won thirteen competitions, and was sometimes defeated by Sophocles; Euripides won four.

The most famous tragedies of Sophocles feature Oedipus and Antigone: they are generally known as the Theban plays, though each was part of a different tetralogy (the other members of which are now lost). Sophocles influenced the development of drama, most importantly by adding a third actor (attributed to Sophocles by Aristotle; to Aeschylus by Themistius), thereby reducing the importance of the chorus in the presentation of the plot. He also developed his characters to a greater extent than earlier playwrights.