Docker Desktop overview - Step-by-Step Execution

Process Flow - Docker Desktop overview

Start Docker Desktop

↓

Docker Engine starts

↓

User runs Docker commands

↓

Docker Desktop manages containers/images

↓

Containers run apps in isolated environments

↓

User stops Docker Desktop

→Docker Engine stops

This flow shows how Docker Desktop starts the Docker Engine, manages containers and images, and stops cleanly.

Execution Sample

Docker

docker run hello-world

docker ps

docker stop <container_id>

These commands run a test container, list running containers, and stop a container.

Process Table

Step	Command	Action	Result/Output
1	docker run hello-world	Docker Desktop starts container from image	Hello from Docker! (test message)
2	docker ps	List running containers	Shows 'hello-world' container if still running
3	docker stop <container_id>	Stops the running container	Container stops, no longer listed in docker ps

💡 User stops container or Docker Desktop, ending container lifecycle

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3
Docker Engine	Stopped	Running	Running	Running
Containers	None	hello-world running	hello-world running	None
Images	None	hello-world image present	hello-world image present	hello-world image present

Key Moments - 2 Insights

Why does 'docker run hello-world' show a message and then stop?

The 'hello-world' container runs a small program that prints a message and exits immediately, as shown in step 1 of the execution_table.

Why does 'docker ps' sometimes show no containers after running hello-world?

'docker ps' lists only running containers. Since 'hello-world' stops right after running, it disappears from the list as shown in step 2 and 3.

Visual Quiz - 3 Questions

Look at the execution_table, what is the output of 'docker run hello-world' at step 1?

A Error message

B List of running containers

C Hello from Docker! (test message)

D No output

💡 Hint

Check the 'Result/Output' column in row for step 1 in execution_table

At which step does the container stop running according to the variable_tracker?

A After Step 3

B After Step 2

C After Step 1

D At start

💡 Hint

Look at 'Containers' row in variable_tracker after each step

If Docker Desktop was not running, what would happen when running 'docker ps'?

A It would list containers normally

B It would show an error because Docker Engine is stopped

C It would start Docker Engine automatically

D It would show empty list without error

💡 Hint

Refer to 'Docker Engine' state in variable_tracker and how Docker commands depend on it

Concept Snapshot

Docker Desktop runs Docker Engine on your computer.
You use Docker commands to manage containers and images.
Containers run apps isolated from your system.
'docker run' starts containers; 'docker ps' lists running ones.
Stopping containers removes them from running list.
Docker Desktop must be running for Docker commands to work.

Full Transcript

Docker Desktop is a tool that runs the Docker Engine on your computer. When you start Docker Desktop, the Docker Engine starts running in the background. You can then use Docker commands like 'docker run' to start containers, which are isolated environments running applications. For example, running 'docker run hello-world' starts a small container that prints a welcome message and then stops. Using 'docker ps' lists running containers, but since 'hello-world' stops quickly, it may not appear. You can stop containers with 'docker stop'. Docker Desktop must be running for these commands to work because it manages the Docker Engine and container lifecycle.