Container.
A lightweight, stand-alone, executable package that includes everything needed to run a piece of software, including the code, a runtime, libraries, environment variables, and config files.
Image.
A snapshot of a container that contains the application and all its dependencies. The image is used to create a container.
Docker file.
A text document that contains all the commands a user could call on the command line to assemble an image.
Compose.
Volume.
A persistent data storage unit that can be attached to containers to keep data persistent across container lifecycles and restarts.
Docker Engine.
The core of Docker, it is a client-server application with a server side daemon process that creates and manages Docker containers.
Docker Hub.
A cloud-based registry service that allows you to link to code repositories, build your images, test them, store manually pushed images, and link to Docker Cloud.
Docker Compose.
A tool for defining and running multi-container Docker applications. With Compose, you use a YAML file to configure your application's services.
Docker Swarm.
A clustering and scheduling tool for Docker containers. With Swarm, IT administrators and developers can establish and manage a cluster of Docker nodes as a single virtual system.
Registry.
A storage and content delivery system, holding named Docker images, available in different tagged versions.
Layer.
Each instruction in a Dockerfile creates a layer in the image. Layers are stacked on top of each other to create a final image.
Docker Daemon.
The background service running on the host that manages building, running and distributing Docker containers.
Docker Client.
The command line tool that allows the user to interact with the Docker daemon.
Docker Namespace
A technology that provides isolation for Docker containers. Each aspect of a container runs in a separate namespace and its access is limited to that namespace.
Docker Machine
A tool that lets you install Docker Engine on virtual hosts, and manage the hosts with docker-machine commands.
Docker Network
An internal network that connects your Docker containers to each other and to the outside world.
Orchestration
The automated configuration, coordination, and management of computer systems and software. In the context of Docker, tools like Docker Swarm and Kubernetes help in orchestrating containers.
