What I have understood about Machine Learning so far

This quote simply explains the complexity of Human Brain, Human brain is made up of billions of thinking units called Neurons, a single Neuron in brain is connected to several other Neurons through links just like electrical wires known as Axon, these axons provide a path for electrical impulses to move between individual neurons and thus knowledge moves on the form of electrical impulses in our brain. As many of you know Artificial intelligence is one of the hottest areas of research these days, it mainly deals with creation of man-made intelligent systems. We, Human beings are intelligent because we have the ability to gain knowledge, which forms core part of intelligence, practically it's very difficult for computers to gain knowledge because they are just made out of sand (Silicon), but how can they learn and gain knowledge? How can they become intelligent? How can they gain potential to influence our everyday life in the near future?