For an introduction to neural nets, you will be viewing a series of online videos created by Grant Sanderson, author of the 3Blue1Brown site that "... centers around presenting math with a visuals-first approach." The videos present visualizations of the concepts behind neural networks before describing the mathematics underlying their function. There are four videos in the series, and the last one is optional.

Lecture Videos

The following link takes you to the playlist of four videos on YouTube:

• Neural networks

The core parts of each video span the time windows listed below, and the last video is optional:

• But what is a Neural Network? (19:13) (view up to 16:26)
• Gradient descent, how neural networks learn (21:01) (view up to 16:35)
• What is backpropagation really doing?? (13:54) (view up to 12:27)
• Backpropagation calculus (10:18) (optional)