what is the use of left join in sql code example

Example 1: right join sql

#The RIGHT JOIN keyword Return all rows from the right table (table_name2), even if there are no
#matches in the left table (table_name1). 
syntax->SELECT column_name(s)
FROM table_name1
RIGHT JOIN table_name2
ON table_name1.column_name=table_name2.column_name 
////example////
SELECT Persons.LastName, Persons.FirstName, Orders.OrderNo
FROM Persons
RIGHT JOIN Orders
ON Persons.P_Id=Orders.P_Id
ORDER BY Persons.LastName

Example 2: left join sql

SELECT column_name(s)

FROM table1

LEFT JOIN table2
 ON table1.column_name = table2.column_name;