Dear Roshni,
HR will have to have a good relationship with all the departments in an organisation. Firstly people of various departments are recruited by HR and hence it starts with finding out what the department is all about, how it functions, what are the kind of resources needed etc. Then in Core HR operations as well, HR needs to connect with the other departments for payroll, leaves,confirmation,rewards and recognition etc.
I would like to conclude by saying that HR is one whihc builds and binds with the other departments and continuosly works with them to achecive the company's goals and objectives.
Do let me know if you want more clarity.
Regards
Renu