Docker
A platform for developing, shipping, and running applications in containers.
Definition
Docker is an open-source platform that enables developers to build, package, and distribute applications as lightweight, portable containers. A Docker container includes the application code, runtime, system tools, libraries, and settings needed to run the application. Docker images are built from Dockerfiles ”” text files specifying the environment configuration. Docker Hub is the public registry for sharing container images. Docker changed software development by making application environments reproducible and portable.
Example
“A team uses Docker to package a Python microservice with all its dependencies, ensuring the same image runs on every developer's machine and in production.”
Usage Examples
- 1
“The team applied docker best practices to improve their cloud computing outcomes significantly.”
- 2
“Understanding docker is essential for anyone building a career in IT & Technology.”
🧪 Try it · Practice playground
🐳 DockerA minimal Node Dockerfile
Each instruction creates a cached layer. Order matters: copy package.json before the rest so `npm ci` is re-used when only source code changes.
$ docker build -t myapp . [+] Building 18.4s => [1/5] FROM node:20-alpine => [2/5] WORKDIR /app => [3/5] COPY package*.json ./ (cached) => [4/5] RUN npm ci --omit=dev (cached) => [5/5] COPY . . => exporting to image => => writing image sha256:9c7… => => naming to docker.io/library/myapp $ docker run -p 3000:3000 myapp Server listening on :3000
💡 `npm ci` is faster and more reproducible than `npm install` because it reads only package-lock.json.
When & How to Use
Use 'Docker' when working in Cloud Computing contexts where docker is an open-source platform that enables developers to build, package, and distribute applications as lightweight, portable containers.
- ▸Applying docker principles during a cloud computing project or initiative
- ▸Explaining docker to a junior team member or stakeholder unfamiliar with IT & Technology
- ▸Evaluating options or proposals using docker as a decision-making criterion
Etymology & Origin
The term 'Docker' derives from professional usage and entered IT & Technology professional usage as the field formalised in the 20th century.
History & Evolution
The concept of docker has evolved alongside IT & Technology. Early practitioners relied on informal methods; structured approaches emerged with the professionalisation of cloud computing in the mid-20th century. Today, docker is a standard part of IT & Technology practice globally.
Synonyms
- container platform
- container engine
- container runtime
Antonyms / Opposites
- virtual machine
- bare metal deployment
Images
CC-licensed · free to useVideo
Related Terms
- container
- kubernetes
- dockerfile
- docker-hub