Since 2013 I've built, managed and even hosted LAMP servers.
What is a LAMP Server?
LAMP stands for Linux, Apache, MySQL and PHP. Superior to it's predecessor, client/server architecture, it can handle thousands of requests per second.
Linux is an open-source operating system, meaning you can build a server for the price of hardware alone.
You can rebuild a server with new hardware and not have to pay for another Windows license.
I've even seen linux handle taking a drive from one motherboard and connect it to a different board and run, no problems. Although this normally works best with the same chipset, it is still amazing and handy.
Apache is an open-source server for shelling out web pages.
MySQL is an open-source database which is extremely reliable.
PHP was invented in 1994 and become extremely popular in the past 20 years for building LAMP applications. It's fast and flexible.
I've been programming in PHP for almost 20 years now.
In-House Linux Servers
Our in-house servers included an optical fiber connection to the Internet. We had a UPS feeding pure sinewave power to our servers to eliminate any power noise. It was great, but eventually everything must change.
Yes, everything today is in "the Cloud" and it's great. More reliable clusters watching for failing hardware 24/7 is a beautiful thing.