A Docker container is a type of virtualization technology that allows you to run applications and services in a secure, isolated environment. It is a lightweight, portable, self-contained software package that includes everything needed to run an application: code, runtime, system tools, system libraries, and settings.
For example, if you wanted to run a web application, you could create a Docker container with the necessary web server, database, and other components. This container can then be deployed on any computer or cloud server, regardless of the underlying operating system.