SQL Joins - INNER, OUTER, LEFT and RIGHT

Here is a simple post from Eswar explaining why and where to use SQL join. Please check the below link to view the post:

Writing SCCM Reports using SQL Joins

http://eskonr.com/2012/08/writing-sccm-reports-using-sql-joins/

For more detailed information on SQL joins, Check the below post by Suresh Dasari:

Joins in sql server, Inner Join, Cross Join, Left Outer Join, Equi join, Right Outer Join, Full Outer Join

http://www.aspdotnet-suresh.com/2011/12/different-types-of-joins-in-sql-server.html