One category refers to the older generation of employees with historical significance. For example, employees at the beginning of postal enterprises or before the separation of posts and telecommunications. Such employees are generally old employees who do not implement the labor contract system. The second category refers to: after entering the full-time labor contract system, the employees recruited by the unit are subject to labor contract management and the labor contract law is applicable.
The third category refers to: labor dispatch workers or low-end employees who cannot serve as middle and high-level employees.