Video What is an artificial neural network?

3Blue1Brown by Grant Sanderson has a series of 4 videos on neural networks which is easy to watch, fun, and does an excellent job at introducing the functioning of a simple neural network.

This first video (19 min) introduces neural networks.

Watch it beyond the acknowledgement fragment as the function ReLU (a really important function in modern neural networks) is introduced at the very end.

Note:   As you develop your own ML models, if you find that your mathematical background is shaky, 3blue1brown also has an excellent series of videos on linear algebra and an equally great one on calculus.