Jenkins is an open source automation server. It helps automate the parts of software development related to building, testing, and deploying, facilitating continuous integration and continuous delivery. It is a server-based system that runs in servlet containers such as Apache Tomcat.Jenkins is used to build and test your product continuously, so developers can continuously integrate changes into the build. Jenkins is the most popular open source CI/CD tool on the market today and is used in support of DevOps, alongside other cloud native tools.