Martin Luther King did so much and means so much to so many people that it will be difficult to say who he is and what he as done. In light of this, this answer will only be a short summary of the man.
Martin Luther King was born in 1929 and died in 1968. He was a minister, activist and a central proponent of the civil rights movement in the America. He is also a icon, an inspiration, and role model. He is famous for his speeches, which stirred America and his words still do, like his famous, "I have a dream" speech, or his words in the work, "A Letter from a Birmingham Jail." He is also famous for his marches and demonstrations. But perhaps he is most known for his method of seeking change.
He like, Mahatma Gandhi, advocated non-violent demonstrations. By doing this, he was able to show that his opponents were the violent ones. In 1964, he was the youngest recipient of the Noble Peace Prize. On April 4 in 1968 he was assassinated, but his legacy lives on.