Plato was a classical Greek philosopher born around 427/428 BCE, a student of Socrates, and the teacher of Aristotle. He founded the Academy in Athens, one of the earliest institutions of higher learning in the Western world. Plato's writings, primarily in the form of dialogues, cover a wide range of subjects, including philosophy, politics, and metaphysics, with notable works like "The Republic" outlining his vision of an ideal state.