When creating a data warehouse, it is common for data from disparate sources to be brought together in one place so that it can be analyzed for patterns and insights. It would be great if data from all these sources had a compatible schema from the outset, but this is rarely the case. ETL takes data that is heterogeneous and makes it homogeneous. Without ETL it would be impossible to programmatically analyze heterogeneous data and derive business intelligence from it. Informatica is a powerful ETL tool that accomplishes this task.