A Dockerfile is a text file that contains instructions for building a Docker image. It is used to define the environment and configuration of an application or service, including the software dependencies and runtime settings.
The Dockerfile starts with a base image, which can be a pre-existing image from the Docker Hub or a custom image. The instructions then specify how to configure and install additional software packages, copy files into the container, and set environment variables.
Once the Dockerfile is complete, it is used to build a Docker image using the “docker build” command. This creates an immutable snapshot of the application or service that can be deployed and run on any machine that has Docker installed.
Dockerfiles are essential for creating portable applications that can be easily moved between development, testing, and production environments. They provide a consistent way to package and distribute applications across different platforms and ensure that they run in a predictable manner.
