Docker Simplified: for Beginners

What Is a Docker?

1. Let’s Say you created an application, and that’s working fine in your machine.???????

Figure 1: App Working Fine

 

2. But in production it doesn’t work properly, developers experience it a lot.

Figure 2: Not Working in Production

 

3. That is when the developer’s famous words are spoken

Client: Your application is not working

Developer: It works on my machine

Figure 3: Client Developer

 

4. The Reason could be due to:
   1. Dependencies
   2. Libraries and versions
   3. Framework
   4. OS Level features
   5. Microservices

That the developer’s machine has but not there in the production environment.

 

5. We need a standardized way to package the application with its dependencies and deploy it on any environment.

Docker is a tool designed to make it easier to create, deploy, and run applications by using containers.

Figure 4: Docker Icon

 

How does docker work?

1. Docker packages an application and all its dependencies in a virtual container that can run on any server.

   

   Figure 5: Container
    

2. Each container runs as an isolated process in the user space and take up less space than regular VMs due to their layered architecture.

   

   Figure 6: Architecture
    

3. So, it will always work the same regardless of its environment.

Credit Goes to @codechips