This document discusses SQL Server Integration Services (SSIS), an extract, transform, load (ETL) tool from Microsoft. It provides an overview of what ETL is and the typical steps involved, including extracting data from sources, transforming the data, and loading it into a destination. The document then describes the key components of SSIS, such as the SSIS designer, runtime engine, tasks, data flow engine, API/object model, and packages. It also lists some common uses of SSIS, such as merging data, populating data warehouses, cleaning data, and automating data loads.