Opensource.com - https://opensource.com/article/18/2/how-kubernetes-became-solution-migrating-legacy-applications
In the early days of the internet, if you wanted to launch an application, you had to buy or rent hardware. This was a physical server or a rack of servers, and you needed one server per application, so it was expensive. In 2001, VMware came out with virtualization—software that allowed users to run multiple applications on the same hardware. This meant you could split up a single box into multiple virtual boxes, each running its own environment and applications. The cost savings for businesses were tremendous.