If you said Lithium, which has half the density of water, you'd be wrong. The answer is graphene aerogel, which holds the world record as the least dense solid.

Artificial Intelligence (AI) is a broad term used for intelligence that is non-biological (machine intelligence). AI is made up of various disciplines, one of them is Machine Learning (ML). Machine learning is one of the most common forms of AI to which we are normally exposed. When you use your phone and ask it a question, your phone is using ML (and natural language processing) to provide you the best answer it has learned. Typing corrections, which are tailored to your typing habits, are also a result of...