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.
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.