It's refreshing to see a page with Last-Modified actually showing the date the document was last modified. Nowadays, too many websites report the current date even when no single byte of the content is changed since publication.

I have completed this tutorial by Micheal Nielsen and it has enormously supplemented my understanding of the subject. The good part is that it just had enough mathematical rigour the subject demands.

I didn't get lost in the details and was able to see the bigger picture after going through his work. It has brought in enormous change to my career and life. I can't thank him enough.

Just adding a +1 for http://neuralnetworksanddeeplearning.com/. It is really excellent. Clear, but mathematically rigorous. Highly recommended.

Agreed - it gives a very solid overview of the field. Truth be told, it was a bit too mathematically rigorous for my taste, so I had trouble producing code for backpropagation. However with the second link (backpropagation step-by-step, with numbers so you can check progress) and then TensorFlow Jupyter notebooks I think I cracked it. Now I just an excuse to use ANN at work... ;)

Wonder where OP got the idea that this was from 2007.