Continuous integration is a process in which all development work is integrated as early as possible. The resulting artifacts are automatically created and tested. This process should identify errors as very early in the process.
Jenkins is one open source tool to perform continuous integration and build automation. The basic functionality of Jenkins is to execute a predefined list of steps. The trigger for this execution can be time or event based. For example, every 20 minutes or after a new commit in a Git repository.
The list of steps can, for example, include: