JOIN clause is extremely important in SQL language. It joins rows from two or more tables.
You need my MySQL installed on your local machine.
You need Chinook database as well since the examples are based on Chinook.
As usual, start the server, connect to the server, display the databases, select Chinook, and show its tables.
service mysql start mysql -u root -p mysql> show databases; mysql> use Chinook; mysql> show tables;