Q1. List out all INSTRUCTION statement of dockerfile and give one line explanation.

FROM -It should be the first instruction in the Dockerfile. It is used to specify our base layer from which we are creating the image.
MAINTAINER – It is used to set the author.
RUN – It is used to run a command in shell.
CMD – It provides a default executable for a container.
LABEL – It is used for putting some metadata in a container.
EXPOSE – Expose a port and listens to it.
ENV – Used to set the environment variables.
ADD – Add new files and directories to filesystem.
COPY – Copies files and directories from src to dest.
ENTRYPOINT – Allows you to configure a container that will run as an executable.
VOLUME – Creates a mount point.