FROM : Set base image
MAINTAINER : Author of docker file
RUN : Run the commands in new layer
VAR : Used to set variable, we can re-use these variables later
EXPOSE : specify port of the container
COPY : Copy files to the container
ADD : copy files into container and extract it
USER : Set the runtime user
ENV : set environment variable
CMD : to set PID1
ENTRY POINT : to set PID1
WORK DIR : set the working directory