Docker · Module 1 of 10

What is a container?

Containers package an app with everything it needs so it runs the same everywhere.

📖 Key ideas

A container is an isolated process that carries its own files, libraries and settings.
Containers share the host operating system kernel, so they start in seconds and use little memory.
A virtual machine includes a whole guest OS; a container does not.
Docker is the most popular tool to build and run containers.
Containers end the "it works on my machine" problem.

💡 Real-life example: Like a lunch box: the meal and its spoon travel together, so you can eat it in any office.

ContainerAn isolated running app with its own files

HostThe machine that runs the containers

KernelThe OS core that containers share

Virtual machineA full computer with its own guest OS