The best way to learn about JOINS is the example. So below is the example to demonstrate JOINS
Suppose that there are two tables
1- Person
2-Information
Person table has definition and data like  that
Person:

Information:

mysql> select * from person;

out put:

3 rows in set (0.00 sec)

mysql> select * from information;

5 rows in set (0.00 sec)

Regular Join:

If apply a regular JOIN (with out use of these keywords INNER, OUTER, LEFT or RIGHT), then I get all records that match in the appropriate way in the two tables, and records in both incoming tables that do not match are not reported:

mysql> select name, phone, address

from person join information

on person.number = information.number;

OR

mysql> select name, phone, address

from person,information where

person.number = information.number;

Output:

4 rows in set (0.01 sec)

LEFT JOIN:
If I apply left joint with using keyword LEFT JOIN

mysql> select name, phone, address
from person left join information on person.number = information.number;

Output:

5 rows in set (0.00 sec)

RIGHT JOIN:
If I apply right joint with using keyword RIGHT JOIN

mysql> select name, phone, address
from person right join information on person.number = information.number;

5 rows in set (0.00 sec)

OUTER JOIN: Outer join does not support RDBMS.