Short answers, pulled from the story.
Socrates was an ancient Greek philosopher from Classical Athens, born in 470 or 469 BC and dead in 399 BC. He is often called the first Western moral philosopher and was a major inspiration on his student Plato, who largely founded the tradition of Western philosophy.
Socrates authored no texts of his own, and everything known about him comes from the accounts of others. The chief sources are his pupils Plato and the historian Xenophon, the comic dramatist Aristophanes, and Plato's pupil Aristotle, who was born after Socrates's death.
The Socratic problem is the difficulty of reconstructing Socrates's true thoughts because the ancient accounts of him are contradictory. Friedrich Schleiermacher attacked Xenophon's reliability in 1818, and later scholars such as Gregory Vlastos and Charles H. Kahn argued that only Plato's early dialogues, or even just Plato's Apology, carry real historical weight.
In 399 BC Socrates was accused of impiety, called asebeia, and of corrupting the youth of Athens. A jury of hundreds of male Athenian citizens found him guilty by majority vote, and after he proposed his own penalty the jurors ordered death by drinking hemlock.
The Socratic method, or elenchus, is a process of refutation that proceeds through short questions and answers. Socrates asks a supposed expert for a definition of something like virtue or justice, then through further questions exposes that the expert's beliefs are contradictory, most prominent in Plato's early works such as the Apology, Crito, and Gorgias.
Socrates frequently proclaimed his own ignorance, a stance captured in the saying "I know that I know nothing," attributed to him from Plato's Apology. Scholars debate whether he genuinely thought he lacked knowledge or feigned modesty, but there is consensus that acknowledging one's lack of knowledge is the first step toward wisdom.
Almost all philosophical currents after Socrates, except the Epicureans and Pyrrhonists, traced their roots to him, including Plato's Academy, Aristotle's Lyceum, the Cynics, and the Stoics. His influence continued through Islamic scholars, the Italian Renaissance humanists, and modern thinkers such as Kierkegaard, Nietzsche, and Hannah Arendt.