Ever nodded along when someone said "infrastructure" and had no idea what they meant? You're not behind. Most people never got the plain-English version.
A server is just a computer with a job. It's usually bigger and less social than your laptop, and its whole purpose is to run software and answer other computers over a network. Stack a bunch of them together with storage and networking, and that pile is "infrastructure." Your bank, your food delivery app, this email: all running on a pile like that somewhere.
Here's the part that matters for everything that comes next. Every server, anywhere, needs the same four things to do its job. And across bare metal, virtualization and the cloud, only one question really changes: who is responsible for those four things when something breaks?
That question decides who gets the 3 a.m. phone call. Part 1 lists the four and answers it for each era:
It's a 5-minute read, and the rest of the series builds on it.
— JC
