whatis docker
Docker
Also known as: dockerd, Docker Engine
The most widely used container platform, providing tools to build images, run containers, and manage networks and volumes.
What Is Docker in Linux?
Docker popularized containers with a simple CLI and the Dockerfile format. A background daemon, dockerd, runs as root and manages containers; the docker command talks to it over a socket.
Members of the docker group effectively have root on the host, since they can mount the host filesystem into a container. Rootless mode or Podman avoid that.
Example
docker run -d --name web -p 8080:80 nginx
docker psLearn more about Docker
- Docker and Podman: Container Basics on Linux An introduction to running containers on Linux with Docker and Podman: images, containers, the core commands you need day to day, and how the two tools differ.
- Docker Compose Basics: From docker run to Declarative Stacks Docker Compose turns long docker run commands into a version-controlled YAML file describing your whole stack: services, volumes, networks, and environment. Here is the mental model plus a working template.
- Container Networking Explained: Bridges, Ports, and Why Your Containers Cannot Talk Published ports, user-defined networks, DNS between containers, and why binding to 0.0.0.0 exposes a service your firewall thinks is closed.
Related tools
- docker run Builder Build docker run commands with ports, volumes, env vars, and restart policies. Podman-compatible.
- Docker Compose Generator Build a docker-compose.yml with volumes, environment, ports, restart policy, and healthcheck.