Docker Mastery: with Kubernetes +Swarm from a Docker Captain

IaaS is the layer of cloud computing where you rent raw infrastructure through an API, meaning virtual machines, disks and networks, and take responsibility for the operating system and everything you install above it.

PaaS is a hosting layer that takes your source code and turns it into a running application for you, owning the machines, the runtime, the build, the routing, the certificates and the restarts, so that shipping becomes a push rather than a project.

Serverless computing runs your code only while an event is calling it: the provider conjures an execution environment on demand, throws it away afterwards, and charges for work performed instead of for capacity sitting idle.

Git is a distributed version control system that records the history of a set of files as a graph of snapshots, lets many people work on branches of that history at once, and merges their work back together.

HTTP is the request-and-response protocol of the web: a client sends a method, a path and headers, a server answers with a status code, headers and a body, and each exchange stands alone unless the two sides agree to carry state in a header.

A REST API exposes an application's data as resources at stable addresses and lets clients read and change them with HTTP's standard methods and status codes, so that the protocol itself carries most of the meaning.