Continuous integration is a process used to improve the quality of development changes. A continuous integration process, when applied to developers, takes new code changes and integrates it with the rest of the code base. This is done early in the development lifecycle, creating an instant feedback loop and associated pass or failure against the change.
Within the remits of DevOps, continuous integration is a key component as it uses centralized tooling to make changes visible to other users and promotes collaboration and integration of changes earlier in the software development lifecycle. Continuous integration is often coupled with Continuous Delivery processes, where continuous integration is used as the first part of the software delivery lifecycle.
Prior to continuous integration being implemented, developers would sometimes only find out that code changes did not work when a release needed to be packaged. At this point, all developer changes were combined...