Master data management (MDM) is a very broad term and is seen materialized in a variety of ways. For the scope of this document it serves more as a context of data quality than an activity that we actually target with DataCleaner per-se.
The overall goals of MDM is to manage the important data of an organization. By "master data" we refer to "a single version of the truth", ie. not the data of a particular system, but for example all the customer data or product data of a company. Usually this data is dispersed over multiple datastores, so an important part of MDM is the process of unifying the data into a single model.
Obviously another of the very important issues to handle in MDM is the quality of data. If you simply gather eg. "all customer data" from all systems in an organization, you will most likely see a lot of data quality issues. There will be a lot of duplicate entries, there will be variances in the way that customer data is filled, there will be different identifiers and even different levels of granularity for defining "what is a customer?". In the context of MDM, DataCleaner can serve as the engine to cleanse, transform and unify data from multiple datastores into the single view of the master data.