11. How HTTP works ? What is HTTP/2?

As FrontEnd engineers, we'd better understand how HTTP works.

In case you are not familiar, here are some materials

https://developer.mozilla.org/en-US/docs/Web/HTTP/Overview

https://developers.google.com/web/fundamentals/performance/http2

https://www.digitalocean.com/community/tutorials/http-1-1-vs-http-2-what-s-the-difference

HTTP/2 helps with the performance improvement of resource loading. It could be a shining point if you can integrate this in your answers on general questions on performance tuning.