Docker

Docker is an open-source ✕ Open source is software whose source code is public: anyone can view, use, modify and share it. It favours transparency and avoids depending on a single vendor. More in the glossary → platform used to build, package and run containers ✕ A container packages an application with everything it needs to run — code, libraries, dependencies — in an isolated bundle, so it behaves the same in any environment. More in the glossary → , and it is the tool that made this technology popular and accessible. With Docker, an application and all its dependencies are described in a file called a Dockerfile, from which an image is built: an immutable template. That image then runs as a container, identical on any machine that has Docker. This removes the problem of environment differences and speeds up both development and deployment. Images are shared through registries like Docker Hub, which makes it easy to reuse other people’s software. To orchestrate many containers in production it is usually combined with Kubernetes ✕ Kubernetes is an open-source system that manages and orchestrates containers at scale: it automates their deployment, load distribution and recovery from failures across many servers. More in the glossary → . It is a fundamental tool in modern development and infrastructure.