Neural networks are networks of nerve cells in the brains of humans and animals. The human brain has about 100 billion nerve cells. We humans owe our intelligence and our ability to learn various motor skills and intellectual capabilities to the brain’s complex relays and adaptivity. The nerve cells and their connections are responsible for awareness, associations, thoughts, consciousness and the ability to learn. Mathematical models of neural networks and their implementation on computers are nowadays used in many applications such as pattern recognition or robot learning. The power of this fascinating bionics branch of AI is demonstrated on some popular network models applied to various tasks.