Referring to the development of software systems, DevOps has been broadly defined as “a set of practices intended to reduce the time between committing a change to a system and the change being placed into normal production, while ensuring high quality”.
DevOps includes practices such as continuous integration, continuous automated testing, and automated deployment to ensure speed, quality, stability, and reliability.
DevOps is a cultural shift within many organizations. The historical separation between software development and IT operations is removed by having all participants contribute to the entire software development lifecycle. They are aligned around shared goals of fast delivery, high quality, and customer expectations.
Background of the term:
DevOps is a portmanteau of the two words development and operations that refer to software development and IT operations.
What is DevOps?
 DevOps: A Software Architect’s Perspective, 1st ed. by Bass, Weber, and Zhu.