Drama, Tragedy
The Ancient Greeks more or less invented the idea of a 'genre', so with Sophocles, you’re looking at some of the very first examples of drama and tragedy. It’s a drama because it is meant to be acted out before an audience, and a tragedy because it’s about the death of a great person (Oedipus) because of an overpowering force (fate).
Sophocles, one of the very first tragedians (people who write tragedies), is a pretty big deal for Western literature. His work is one of the only examples we have of Greek tragedy, which is the foundation for modern theatre, and even movies.
The gist is, basically, you have a hero who’s a pretty good guy overall but also has a fatal flaw. In Oedipus’ case, it’s that his parents tried to avoid their fate. So it’s not even his fault. But that’s not important in Greek tragedy; there’s no shoulda coulda woulda. That fatal flaw ultimately leads to the death of the hero. Bring sure to bring some tissues to the next Greek tragedy you attend; trust us, you’re going to need it. We learned the hard way.