Can you explain what a Docker container is and how it works?

A Docker container is a lightweight, isolated environment for running applications. It leverages the operating system's capabilities to isolate processes and resources, allowing applications with their dependencies to run in a single package. Docker containers are run from images that contain everything needed for the application to operate: code, libraries, configurations. This ensures portability and consistency of the environment across different machines and stages of development.

Example: if you have a web application, you can package it together with the required version of Python and libraries into a Docker image, and then run this container on any server with Docker installed without additional configuration.