What is the purpose of a Dockerfile when building Docker images in containers?

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A Dockerfile is used to launch and run a Docker container, providing runtime parameters and environment variables.

A Dockerfile is a containerization tool used to secure Docker containers and prevent unauthorized access.

A Dockerfile defines the configuration of a Docker container, specifying the base image, adding files, and running commands to create a custom image.

A Dockerfile is only necessary when pulling pre$-$built Docker images from the Docker Hub repository.