Legal analysis: 1. Different connotations: social security includes different types of insurance, such as medical care and pension, while provident fund is used for housing loans and other funds. 2. Different payment ratios: social insurance has different payment ratios for each type of insurance, while the provident fund is paid by units and individuals at 12% respectively. 3. The payment subjects are different: the pension insurance and medical insurance are paid by individuals, and the rest are paid by units, while the provident fund is not compulsory.

Legal basis: Article 24 of the Regulations on the Management of Housing Provident Fund, employees can withdraw the balance of their housing provident fund accounts under any of the following circumstances:

(1) purchasing, constructing, renovating or overhauling their own houses;

(2) retired;

(3) completely losing the ability to work and terminating the labor relationship with the unit;

(4) leaving the country to settle down;

(5) repaying the principal and interest of the house purchase loan;

(6) the rent exceeds the prescribed proportion of family wage income.

in accordance with the provisions of items (2), (3) and (4) of the preceding paragraph, the employee housing provident fund account shall be cancelled at the same time. If an employee dies or is declared dead, the employee's heirs and legatees may withdraw the storage balance in the employee's housing provident fund account; If there is no heir or legatee, the storage balance in the employee housing provident fund account will be included in the value-added income of the housing provident fund.