Dear Siddu,
Please check below link which is give you simple Example
http://sqlfiddle.com/#!2/3f8c6/2
In that I create one table name of Employee and insert multiple Record on that table, on that now I can group department to check how much type of Department we have.
CREATE TABLE Employees
(
EmpId int auto_increment primary key,
EmployeeName varchar(50),
DepartmentName varchar(50)
);
INSERT INTO Employees
(EmployeeName, DepartmentName)
VALUES
('Employee1','Technical Support'),
('Employee2','Developer'),
('Employee3','Developer'),
('Employee4','Tester'),
('Employee5','Tester');
select EmpId,EmployeeName,DepartmentName from Employees
GROUP BY DepartmentName