Who is the Dajal, the one-eyed deceiver, and what role does he play in Islamic eschatology?

In Islamic eschatology, the Dajjal is a figure who is believed to be a one-eyed deceiver who will appear before the Day of Judgment. He is considered a false messiah who will spread chaos and deception, leading people away from the true path of Islam. Muslims are warned to be wary of his tricks and falsehoods, as he represents a major test of faith before the final judgment.