How to download and run Jenkins
Download Jenkins.
Open up a terminal in the download directory.
Run java -jar jenkins.war --httpPort=8080.
Browse to http://localhost:8080.
Follow the instructions to complete the installation.
When the installation is complete, you can start putting Jenkins to work!
Jenkins pipeline definition
Jenkins Pipeline provides an extensible set of tools for modeling simple-to-complex delivery pipelines "as code". The definition of a Jenkins Pipeline is typically written into a text file (called a Jenkinsfile) which in turn is checked into a project’s source control repository.