Business intelligence Question:

ETL (Extract Transform Load) is used to extract data from various sources. Transform the data which means applying business rules and performing data cleaning (the latter being often overlooked that causes issues) and Load the clean data into data warehouse. Sometimes in ETL there is also master data management element so it can extract data, perform transformation and it may use proper tools to perform data cleansing and check business rules. In recent versions of SQL Server (including 2012) we can have Master Data Services (MDS) and Data Qaulity Services (DQS).