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Docker

A platform for packaging and running applications in containers.

Docker introduced the modern container experience: a single CLI that builds an image from a Dockerfile, pushes it to a registry, and runs it as an isolated process on any Linux host with a kernel that supports namespaces, cgroups, and OverlayFS. Before Docker, the underlying kernel primitives had existed for years (LXC, Solaris Zones, FreeBSD jails), but the developer ergonomics of "build once, ship the image, run anywhere" were what put containers into the mainstream from 2013 onwards.

Solomon Hykes first demonstrated Docker at PyCon US in March 2013 while it was still a side project at the dotCloud platform-as-a- service company. The runtime that Docker originally bundled has since been factored out as the containerd daemon and runc OCI runtime, both governed by the Cloud Native Computing Foundation, so much of Docker's plumbing is now shared with Kubernetes, Podman, and other engines.

Docker Engine and the docker CLI remain the most familiar developer-facing container tool, especially for local development, small Docker Compose deployments, and CI build steps. The Docker Desktop product (paid for larger commercial users) packages an embedded Linux VM with the engine on macOS and Windows.

Debian/Ubuntu: sudo apt install docker.io
Fedora/RHEL:   sudo dnf install docker
Arch:          sudo pacman -S docker
macOS:         brew install --cask docker
Or follow the official Docker Engine instructions at https://docs.docker.com/engine/install/