Artificial intelligence (AI) can be assistants of human or mimic human's behavior, like self-driving cars, robotic arms, smart platform for long-term care, etc. Its powerful ability induces people's concerns on several fields, computer science, robotic machines, financial markets, philosophy, and religion. Moreover, AI may or may not have the mind of a human or social behavior of human in future. This article tries to explain AI from the deep learning in the sense of weak AI through the three components in machine learning, program, data and filters. Meanwhile, this background knowledge provides the opportunity to probe the connection between the week AI and strong AI.