Neural Networks are collection of Neurons containing specific algorithm which are networked together to solve a particular set of problems irrespective of data size.
How Neural Networks(NN) learn
There are three ways neural networks Learn.
Supervised Learning is where a computer algorithm is trained on input data that has been labeled for a particular output .
Unsupervised Learning is in which a system learn through data-sets created by its own. In unsupervised is not labeled.
Reinforcement Learning Learning through feed-back or trial and error method is called Reinforcement learning.