http://cs231n.github.io/gce-tutorial/

https://www.youtube.com/playlist?list=PLQVvvaa0QuDfGVb3yucqvKtUgwOJgZWCm
p2:
https://www.youtube.com/playlist?list=PLQVvvaa0QuDfGVb3yucqvKtUgwOJgZWCm
p4:
https://www.youtube.com/watch?v=-13yIXiyFAs
p5:
https://www.youtube.com/watch?v=6wlzeDaIGtw