From Wikipedia: "Deep learning (deep machine learning, or deep structured learning, or hierarchical learning, or sometimes DL) is a branch of machine learning based on a set of algorithms that attempt to model high-level abstractions in data by using multiple processing layers with complex structures, or otherwise composed of multiple non-linear transformations."

Generally we refer to neural nets with multiple hidden layers. (or RBMs)

A good place to start: https://developer.nvidia.com/deep-learning-getting-started

Deep learning also can be learning principles. Several processes are involved. See attachment for a good place to start.

http://faculty.coehd.utsa.edu/pmcgee/nlii/LOBloomsMcGee.doc

May be this link:

https://devblogs.nvidia.com/parallelforall/deep-learning-for-computer-vision-with-matlab-and-cudnn/

May be following link:

https://www.technologyreview.com/s/513696/deep-learning/

http://machinelearningmastery.com/what-is-deep-learning/

http://deeplearning.net/tutorial/

http://deeplearning.net/

"Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning." - Albert Einstein