4 lessons
What happens when you run your code
Processes, ports and localhost: the three ideas underneath every "it runs on my machine" moment.
What is a server, really
Why "server" is a role any machine can play, and what changes when you actually put one on the internet.
The journey of a request
Following one HTTP request from a browser tab all the way to your server and back, hop by hop.
What breaks first under real traffic
The four resources every server has a limited supply of, and how to tell which one is actually failing.