Installation
Ready to get started using Docker? Great! Head on over to the Docker Desktop webpage. When you arrive, the webpage should look like this — go ahead and click “Windows”. This should begin downloading the installation file.
Once the download is complete, double-click the installer file — unless you specified otherwise, the file is likely located in your Downloads directory (C:\Users\<username>\Downloads).
When the file opens, you’ll see a splash screen. Follow the on-screen directions until the installation completes. Congratulations, you’ve installed Docker! At this point we have two options. We can start working with Docker right away in a command line terminal, or we can work with Docker in a code editor like Microsoft Visual Studio. Since the second option gives us a more visual representation of Docker to begin with, let’s start there.
Exploration: Using the GUI
Open the Docker application, and let’s get started. The first screen you’ll see is the default Docker Desktop screen:
The Home screen is simple with a lot of useful links. The toolbar on the left shows different portions of the Docker Desktop application including Home (where you are now), Containers, Images, Volumes, and Dev(eloper) Environments.
Below that, there’s a section for Extensions (currently in Beta testing), which we’ll get into later. And below that, we see a green bar with a miniature Docker symbol — the green bar tells us that Docker desktop is up and running!
In the middle of the screen, we see a list of popular images, a term we remember from the left-hand side. On the right, there are additional links for installing extensions, a quick start, and links to other Docker-related items. Let’s start by looking at the left-hand side image.
Docker Desktop pages
To start, many of the portions on the left-hand side will not have any content since we have not created any Docker objects yet. But we do see some very helpful tips as to what each one does. The definition of each object is as follows:
- Container: The container packages up code and its dependencies so the application runs quickly and reliably from one computing environment to another.
- Image: An unchangeable file that contains all the relevant information to run the source code (libraries, dependencies, etc.).
- Volumes: Volumes are the preferred mechanism for persisting data generated by and used by Docker containers. When we generate or store data, it will be stored in a Volume.
Admittedly, the definitions of “container” and “image” seem rather similar. So what’s the difference? From the definition, we know everything needed to run a chunk of code exists within the image. Furthermore, the image is built so that it can be run automatically, by itself, without any external dependencies; therefore, an image can run without a container. On the other hand, a container simply stores (and isolates) everything needed to run the script; it is not meant to be downloaded and run as it is. As such, a container cannot run without an image.
Since many of these screens are blank, let’s concentrate on content creation and look at the “Dev Environments” page.
Dev Environments
Using a Dev (or “developer”) environment offers a great deal of flexibility when we’re developing with Docker. To start with, Docker works very well with Microsoft Visual Studio Code which, in turn, gives us access to a large number of features and tools to program with.
Clicking on “Create New Environment”, we’re greeted with a splash screen detailing some advantages of the Docker Developer Environments. Click on “Get Started”. On the next screen, we have two options — we can either create a New Dev Environment using an Existing Git Repo(sitory), or by using a local directory. Additionally, we can use an existing developer environment. Since we’re starting from scratch, let’s choose “New Dev Environment -> Local Directory”.
Clicking “Select”, a dialogue box opens, expecting us to navigate to a folder we’ve already created. For this example, I’ve already created a folder on my Desktop titled “dockfile”. Once I’m within the folder I want to use to store all my Docker files, I’ll click “Select Folder,” and confirm the destination using the “Select” button again. Once I do this, Docker Desktop begins preparing my Dev Environment; depending on the size of your environment, this can take a moment.
Next, let’s explore our new environment a bit within the Docker Desktop application. In the meantime, If you found this content helpful please feel free to Like, comment, and subscribe!
Get new content delivered directly to your inbox.
Aaron J. Pung, Ph.D. 