How to Create a Hello World Container with Docker

Containers have revolutionized how we build, ship, and run applications. With Docker, you can package applications and their dependencies to ensure consistency across different environments. If you’re new to Docker, this tutorial will guide you through creating a container with Docker:

✅ Installing Rancher Desktop, a free alternative to Docker Desktop
✅ Running a basic Hello World container to test your setup
✅ Create your own Docker image using a Dockerfile
✅ (Bonus) Pushing your image to Docker Hub so others can use it

By the end of this tutorial, you’ll have a working containerized application and the foundational knowledge to start building more complex projects.

Step 1: Install Rancher Desktop

Before running Docker containers, you need a container runtime. Rancher Desktop is a free and open-source alternative to Docker Desktop that provides a full Docker-compatible environment with the bonus of a Kubernetes Node! More on that later.

Install Rancher Desktop

1️⃣ Download Rancher Desktop from rancherdesktop.io
2️⃣ Install it based on your operating system (Windows, macOS, or Linux).
3️⃣ During setup, choose dockerd (moby) as the container runtime (this ensures compatibility with Docker commands).
4️⃣ Verify the installation by opening a terminal and running:

docker version

If Rancher Desktop is set up correctly, you’ll see details about the Docker client and server.

Step 2: Run the Hello World Container with Docker

Next, we need to verify that Docker is working correctly by running the built-in “Hello, World!” container in our terminal.

Run the following command in your terminal of choice:

docker run hello-world

What’s Happening?

• Docker pulls the hello-world image from Docker Hub (if it’s not already on your machine).
• It creates a new container from that image.
• The container executes a small program that prints a success message to the terminal.

If everything is set up properly, you should see some output that looks like this:

Hello from Docker!
This message shows that your installation appears to be working correctly.

Now that Docker is running, let’s create our custom container!

Step 3: Create a Custom Dockerfile

Instead of running a pre-built container, let’s build our own Docker image that prints a custom message.

Create a Project Directory

First, create a new directory for your project:

mkdir hello-world-container && cd hello-world-container

I’m sorry. I am on a Mac. If you are on Linux, this will work. If you are on Windows well, there is always Google to complete the above.

Create a Dockerfile

A Dockerfile is a simple text file that contains instructions for building an image.

Create a new file called Dockerfile:

vim Dockerfile

Add the following content:

# Use a lightweight Linux base image
FROM alpine:latest  

# Set the command to print a message
CMD echo "Hello, World! and Welcome to Cloud with Jason!"

What’s Happening?

• FROM alpine:latest → This uses the Alpine Linux image, a super lightweight operating system ideal for containers.
• CMD echo "Hello, World! and Welcome to Cloud with Jason!" → This tells Docker to execute the echo command when the container starts.

Save the file and exit. I like to use “shift + z z”.

Step 4: Build Your Custom Docker Image

Now, let’s build the Docker image from our Dockerfile.

Run the following command:

docker build -t hello-world-custom .

What’s Happening?

• docker build → This tells Docker to create an image based on the Dockerfile.
• -t hello-world-custom → The -t flag gives the image a tag (name) for easy reference.
• . → The dot tells Docker to look for the Dockerfile in the current directory.

Once built, you’ll see an output confirming that the image was created successfully.

Step 5: Run Your Custom Container with Docker

Now, let’s run our newly built container!

docker run hello-world-custom

If everything is correct, the output should be:

Hello, World! and Welcome to Cloud with Jason!

Congrats! 🎉 You’ve just built and run your first custom Docker container!

Bonus: Push Your Image to Docker Hub

Want to share your container with others? You can push it to Docker Hub so anyone can pull and run it.

Step 1: Set Up a Docker Hub Account

1️⃣ Go to hub.docker.com
2️⃣ Click Sign Up and create a FREE account.
3️⃣ Verify your email and log in.
4️⃣ Create a new repository named hello-world-custom.

Step 2: Log in to Docker Hub

Now, authenticate your local Docker client:

docker login

Enter your Docker Hub username and password when prompted. If successful, you’ll see Login Succeeded.

Step 3: Tag Your Image for Docker Hub

Before pushing, you need to tag the image with your Docker Hub username:

docker tag hello-world-custom <your-dockerhub-username>/hello-world-custom

Replace <your-dockerhub-username> with your actual Docker Hub username.

Step 4: Push Your Image to Docker Hub

Now, upload your image to Docker Hub:

docker push <your-dockerhub-username>/hello-world-custom

Once complete, your image is publicly available! 🎉

Now, anyone can pull and run your container using:

docker run <your-dockerhub-username>/hello-world-custom

Conclusion – Creating a Container with Docker

You’ve successfully:

✅ Installed Rancher Desktop for container management
✅ Run the official hello-world Docker container
✅ Built a custom Docker image with a Dockerfile
✅ Pushed your image to Docker Hub

Now that you know the basics, try:

• Adding environment variables to customize messages
• Running a web server in a container
• Using Docker Compose for multi-container apps

The cloud is your playground—keep building! 🚀