A simplest Oozie application is consists of a workflow logic file (workflow.xml), workflow properties file (job.properties/job.xml) and required JAR files, scripts and configuration files. Except the workflow properties file, all the other files should to be stored in a HDFS location. The workflow properties file should be available locally, from where Oozie application is submitted and started.
The HDFS directory, where workflow.xml is stored along with other scripts and configuration files, is called Oozie workflow application directory. All the JAR files should be stored under a /lib directory in the oozie application directory.
The more complex Oozie applications can consist of coordinators (coordinator.xml) and bundle (bundle.xml) logic files. These files are also stored in the HDFS into a respective Oozie application directory.