South Korean professional Go player Lee Sedol (R) presents the Go game board with his signature to Demis Hassabis, the CEO of Google's London-based AI company DeepMind during a press conference after finishing the final match of the Google DeepMind Challenge Match against Google's artificial intelligence program, AlphaGo, in Seoul, on Tuesday. Google's Go-playing computer program again defeated its human opponent in a final match on Tuesday that sealed its 4-1 victory. [Photo/Xinhua]

Google's Go-playing computer program AlphaGo on Tuesday ended a historic match of the ancient Chinese board game with Go grandmaster Lee Sedol of South Korea by taking a 4-1 lead with its fourth victory in the final match of the best-of-five series.

The final winner was already determined before Tuesday's encounter as Lee lost the first three games of the five-game match. AlphaGo got $1 million in prize, which will be donated to charities.

The human Go champion beat the artificial intelligence (AI), developed by Google's London-based AI subsidiary DeepMind, in the fourth match, but Lee was defeated once again in the final match.