What is the difference between etl tool and olap tools? | ETL Testing Interview Questions

ETL tool is meant for extraction data from the legacy systems and load into specified data base with some process of cleansing data.
Ex: Informatica, data stage ....etc
OLAP is meant for Reporting purpose in OLAP data available in Multidirectional model. so that you can write simple query to extract data from the data base.
Ex: Business objects, Cognos....etc