ANNs consist of a large number of simple interconnected processing elements. These elements operate in parallel, whose function is determined by network structure, connection strengths, and the processing performed at computing elements or nodes. The growth of interest in deep learning was partly due to the failures of traditional programming techniques in "hard" tasks such as machine vision, continuous speech recognition, and machine learning. There have been significant demonstrations of neural network capabilities in vision, speech, signal processing, and robotics. The variety of problems addressed by neural networks is impressive.