Let’s continue with our guides dedicated to Docker. Today we’ll take a detailed look at a topic that is really fundamental for anyone involved in web development: Docker containers. A container is the running instance of an application in an isolated environment that is dynamically allocated resources to run. Inside it, the container has the application to run and everything it needs: runtime, libraries, configuration, etc. What is the difference between an image and a container? A docker image is a static package containing all the resources necessary to run an application. Multiple containers can be launched from a Docker.