Container image - What is the purpose of using the phrase "Container image"?

Question

When reading articles on the Internet and textbooks, they use the above terms and make us confused. When we try to understand emerging technologies, I believe the vocabulary behind them is a key point. So, please help to clarify the following confusion on these terms.

1. Is the usage of "Container image" and "Docker image" similar and interchangeable?
2. Are they different on usage?
3. What is the purpose of the usage of "Container image"?

Answer 1

Docker, Inc. originally created the Docker product, which is a specific implementation of containerization technology,

Docker is a set of platform as a service products that use OS-level virtualization to deliver software in packages called containers.

There are many alternatives to Docker, like Podman, Containerd and etc.

Nowadays, Docker as a product is getting so popular, people often refer to containerisation technology as Docker. Almost like when we talk about search engines, we use Google.

So, I would use Container Image when talking about general containerization technology and use Docker Image when talking about the Docker product specifically.