Dockerfile FROM: base images, tags, and multi-stage builds

FROM - initializes a new build stage and sets the base image.

The FROM instruction defines the base OS image. The FROM instruction is strictly mandatory for all Dockerfiles as the very first uncommented instruction.

It specifies the base image for the Dockerfile. All subsequent instructions perform build operations on top of the specified image. The base image is defined in the form IMAGE:TAG (e.g., debian:wheezy). If the tag is not specified, it defaults to latest, but I strongly recommend always explicitly specifying the version tag to avoid unpleasant surprises. This instruction must be the very first in the Dockerfile.

open_in_new Official docs on the FROM instruction .