PaaS
Problem
You want to run a web application.
You don't particularly care about:
* OS patching,
* VM maintenance,
* web-server installation.
You mainly care about your application.
Solution — Platform as a Service
You deploy the application onto a managed runtime.
Your code ↓ Managed platform ↓ Infrastructure
Core idea: PaaS removes much of the infrastructure and OS management from application teams.