Self-Service Deployment
A self-service deployment is a deployment that does not need anything special (knowledge, skill, technology) to be run by an average user. No handoff needs to happen in order to perform a self-service deployment.
Single Point of Truth
The system is the definitive answer to any question you might have about your technology.
Source Control
A system like GitHub where code can be pushed. Source control accumulates all code changes in a central place where build systems can pull that code to create artifacts and kick off CI/CD.
Staging Environment
An environment that is not production where code can be run and evaluated.