Deep learning is a class of machine learning algorithms that. use a cascade of many layers of nonlinear processing units for feature extraction and transformation.
https://en.wikipedia.org/wiki/Deep_learning
What’s the Difference Between Artificial Intelligence, Machine Learning, and Deep Learning?
https://blogs.nvidia.com/blog/2016/07/29/whats-difference-artificial-intelligence-machine-learning-deep-learning-ai/
Deep Learning: With massive amounts of computational power, machines can now recognize objects and translate speech in real time. Artificial intelligence is finally getting smart.
https://www.technologyreview.com/s/513696/deep-learning/