There are different type of Provident Funds. You can differentiate them by type of fund, controlled by and applicability.
For instance Government maintain PF funds for its employees and mainly employees of government organisation are enrolled in this fund.
EPFO or Employee Provident Fund Organisation handles PF of employees working in private sector companies.
Another fund called PPF or Public Provident Fund can be used by anyone. This was mainly targeted to those not covered under above categories.
Anyone can open a PPF account in any bank or post office.