page_title: Docker Images Test
page_description: How to work with Docker images.
page_keywords: documentation, docs, the docker guide, docker guide, docker, docker platform, virtualization framework, docker.io, Docker images, Docker image, image management, Docker repos, Docker repositories, docker, docker tag, docker tags, Docker Hub, collaboration
Back
# Dockerfile Tutorial
## Test your Dockerfile knowledge - Level 1
### Questions
What is the Dockerfile instruction to specify the base image ?
The right answer was FROM
What is the Dockerfile instruction to execute any commands on the current image and commit the results?
The right answer was RUN
What is the Dockerfile instruction to specify the maintainer of the Dockerfile?
The right answer was MAINTAINER
What is the character used to add comment in Dockerfiles?
The right answer was #
Congratulations, you made no mistake!
Tell the world Tweet
And try the next challenge: Fill the Dockerfile
Your Dockerfile skills are not yet perfect, try to take the time to read this tutorial again.
You're almost there! Read carefully the sections corresponding to your errors, and take the test again!
### Fill the Dockerfile
Your best friend Eric Bardin sent you a Dockerfile, but some parts were lost in the ocean. Can you find the missing parts?
# This is a Dockerfile to create an image with Memcached and Emacs installed.
# VERSION 1.0
# use the ubuntu base image provided by dotCloud
ub
E B, eric.bardin@dotcloud.com
# make sure the package repository is up to date
echo "deb http://archive.ubuntu.com/ubuntu precise main universe" > /etc/apt/sources.list
apt-get update
# install memcached
RUN apt-get install -y
# install emacs
apt-get install -y emacs23
Congratulations, you successfully restored Eric's Dockerfile! You are ready to containerize the world!.
Tell the world! Tweet
Wooops, there are one or more errors in the Dockerfile. Try again.
## What's next?
In the next level, we will go into more detail about how to specify which command should be executed when the container starts,
which user to use, and how expose a particular port.