This document discusses using Big Data applications on OpenStack. It notes that Big Data needs large clusters of servers, which clouds can provide. OpenStack is a popular choice due to its support from major companies and ability to work across public and private clouds. The document outlines common components of Big Data applications, such as HDFS, MapReduce, and data access tools. It introduces Cloudify as an open source platform as a service (PaaS) that can manage and orchestrate all the pieces of a Big Data application deployed on an OpenStack cloud.