A neural network is a system of hardware and/or software that is modeled on the operation of neurons in the human brain. The design behind neural networks is inspired by the human brain and its functionality. Let's understand the design of the human brain. The neuron is the basic working unit of the brain. It's a specialized cell that can transmit information to other nerve cells. The brain is made up of approximately 100,000,000,000 neurons. A neuron's main function is to process and transmit information.