A pipeline in the software engineering world is understood as a chain of events (of processes, components, and so on) that automatically triggers and delivers input to the next element. It resembles the physical pipelines that exist in the real world.
In a CI context, a pipeline is a collection of sequential steps that integrate code from different developers. The chain of events is triggered by a commit or push to a source code repository such as GitLab. The build system (for example, Jenkins or GitLab CI) is notified of a new version, compile, and source code and runs unit testing.
Before we go any further, you should understand that without unit tests, or other automated tests, the effort of integrating pieces of code by different developers is very difficult. So, before you begin building pipelines, make sure that your developers have written test code. That way...