Listing local images in Docker - Step-by-Step Execution

Process Flow - Listing local images

Run 'docker images'

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Docker CLI sends request

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Docker daemon fetches local images

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Daemon returns image list

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CLI displays images in table format

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Done

The command 'docker images' asks Docker to show all local images. Docker daemon fetches and returns the list, then CLI shows it.

Execution Sample

Docker

docker images

This command lists all Docker images stored locally on your machine.

Process Table

Step	Action	Docker CLI Output	Result
1	User types 'docker images' and presses Enter		Command sent to Docker daemon
2	Docker daemon retrieves local images		Fetches image metadata
3	Docker CLI receives image list	REPOSITORY TAG IMAGE ID CREATED SIZE	Ready to display
4	Docker CLI displays images	ubuntu latest 2ca708c1c9cc 2 weeks ago 72.9MB	Image info shown
5	Docker CLI displays images	nginx stable 4bb46517cac3 3 weeks ago 133MB	Image info shown
6	Docker CLI displays images	hello-world latest fce289e99eb9 5 months ago 13.3kB	Image info shown
7	End of list reached		Command completes

💡 All local images listed and displayed, command ends.

Status Tracker

Variable	Start	After Step 2	After Step 3	Final
local_images	empty	fetched list of images metadata	list passed to CLI	displayed to user

Key Moments - 2 Insights

Why do I see multiple images with the same repository name?

Each row shows a different tag or version of the image. See execution_table rows 4-6 where repository 'ubuntu', 'nginx', and 'hello-world' have different tags.

What does the IMAGE ID represent?

IMAGE ID is a unique short identifier for each image version. It helps Docker track images internally, shown in execution_table rows 4-6.

Visual Quiz - 3 Questions

Look at the execution_table row 4, what is the TAG of the 'ubuntu' image?

A latest

B stable

C fce289e99eb9

D 2 weeks ago

💡 Hint

Check the 'Docker CLI Output' column in row 4 for the 'ubuntu' image tag.

At which step does the Docker CLI start displaying the image list?

A Step 2

B Step 4

C Step 3

D Step 7

💡 Hint

Look for the first row where 'Docker CLI displays images' in the 'Action' column.

If there are no images locally, what would the output be after step 2?

A List of images with zero size

B Error message

C An empty list with only headers

D Command hangs

💡 Hint

Docker shows headers even if no images exist, so check what 'local_images' would be in variable_tracker.

Concept Snapshot

docker images
Lists all local Docker images.
Shows repository, tag, image ID, creation date, and size.
Useful to see what images are stored locally.
No arguments needed for basic listing.

Full Transcript

The 'docker images' command lists all Docker images stored locally. When you run it, the Docker CLI sends a request to the Docker daemon. The daemon fetches metadata about all local images and sends it back. The CLI then displays this information in a table showing repository names, tags, image IDs, creation dates, and sizes. Each image can have multiple tags representing different versions. The IMAGE ID uniquely identifies each image. If no images exist, the command shows only the table headers. This command helps you see what images are available on your machine.