Hi Mr. Siddiq,
It's not very clear from your post what procedures and processes you are referring to, as there are many procedures and processes used in the HR department. In fact, various functions of HR have many methods and procedures.
For example, recruitment has different methods and sources such as campus recruitment, recruitment through consultants, job portals, etc.
(Cite Contribution) has correctly pointed out that various laws and regulations are utilized in HR.
Please be a little more specific about what you are looking for so that we can guide you in the right direction.
Regards,
Archna