Structure in SAP HR

There are three structure in SAP HR 

1)Enterprise Structure (Client,Company Code,Personnel Area and Personnel Subarea)

2)Personnel Structure (Employee Group and Employee Subgroup)

3)Organisational Structure (Root Organisation Unit,Organisation Unit,Department,Reporting Structure)

For entering employee personal data,allocation of an employee to the structure is first step.
Example: when we hire a person then we have to allocate him/her with personnel area or personnel subarea and employee group or in employee subgroup this will help to generate default value for payroll system.


Allocation of an employee helps us to understand few things like:


1)Where does employee work like what is his personnel area or subarea?
2)What is his position? 
3)Whether an employee is monthly salaried employee or hourly base?
4)He is reporting to whom?
5)In which employee group he falls?