Docker vs Jenkins

Question

I am wondering how exactly does docker fit into CI /CD. I understand that with the help of containers, you may focus on code, rather than dependencies/environment. But once you check-in your code, you will expect tools like TeamCity, Jenkins or Bamboo to take care of integration build, integration test/unit tests and deployment to target servers ( after approvals) where you will expect same Docker container image to run the built code. However, in all above, Docker is nowhere in the CI/CD cycle, though it comes into play when execution happens at the server. So, why do I see articles listing it as one of the things for DevOps? I could be wrong, as I am not a DevOps guru, please enlighten!

Answer 1

DevOps is work culture that combines the development and operations team for continuous development, continuous testing, continuous delivery,  continuous integration, and continuous monitoring.

On the other hand, Docker is nothing but another tool used to implement this work culture.

Docker encapsulates code and code dependencies in a single unit also known as container that can be run anywhere Docker engine is installed. In terms of Continuous Integration /Continuous Deployment, it can help DevOps Engineers separate Configuration from Code, decrease the amount of time spent doing dependency management etc., can use it to scale (with the help of some other tools of course). The list goes on.