The MDM Server is where the live version of the master data is stored. The MDM Repository contains a working copy of the data, and can be stored locally (that is, on the same machine as the Studio) or remotely, based on a Git or SVN server. The data from the MDM Repository must be deployed to the MDM Server before it can be accessed by users of the Talend MDM Web User Interface.
The MDM Server can be installed in three different modes - with an executable file, a jar file, or a war file and to install it you must deploy it onto a Tomcat application server (the recommended version of Tomcat is 8.0.X). For more information about installing the MDM Server, see Installing the MDM server and Talend Data Stewardship Console manually.