We have seen how to pull a Docker image from DockerHub and run in, now we will see how to create our own Docker image, build and run it.

The first step to create a Docker image is to create a Dockerfile.
Dockerfiles is a text file that contains instructions and steps to create a new Docker image.

A Dockerfile has no extension. If you are using docker on windows use notepad to create a dockerfile while saving select "All type" and save the file name as "Dockerfile".