1. 行政主体对其外部行使公共权力并产生法律效果的行为，称为行政行为。在中国行政法中，具体行政行为的概念确立于1989年《中华人民共和国行政诉讼法》颁布之时。该法将具体行政行为设定为提起行政诉讼的必要条件。《最高人民法院关于贯彻执行{中华人民共和国行政诉讼法}若干问题的意见（试行）》进一步明确了具体行政行为的定义，尽管学界对此 Definition remains controversial, it emphasizes the elements of specific cases, external effects, unilateral actions, and legal consequences. The definition in administrative law emphasizes the legal character of administrative acts.

2. The concept of administrative acts in administrative law and administrative litigation is similar to that of administrative measures. Although the 2000 "Supreme People's Court Interpretation" did not directly define administrative acts, it expanded the interpretation to include not only legal acts but also factual acts, unilateral as well as bilateral acts, beneficial as well as detrimental acts, and rigid as well as flexible acts. This expansion aims to enlarge the scope of administrative litigation in China, which is inspired by German law. However, abstract administrative acts and internal administrative acts are still not within the scope of litigation.

3. Administrative acts can be categorized based on their objects: abstract and specific administrative acts. Abstract administrative acts target undefined administrative management objects, such as administrative normative documents. Specific administrative acts, on the other hand, are directed at specific administrative management objects, such as specific administrative penalty decisions.

4. Administrative acts can be differentiated based on the degree of legal constraint: bound and free-discretionary administrative acts. Bound administrative acts are tightly defined by legal norms, while free-discretionary administrative acts allow administrative bodies more latitude in decision-making.

5. Administrative acts can be distinguished according to their formality: formal and informal administrative acts. Formal administrative acts require specific legal procedures, while informal administrative acts do not.

6. Administrative acts can be categorized based on their initiation: autonomous and responsive administrative acts. Autonomous administrative acts are taken by authorities without prior application from the administrative relative, while responsive administrative acts are taken in response to a request.

7. Administrative acts can be classified based on their impact on administrative relatives: beneficial and adverse administrative acts.

8. Administrative acts can be differentiated based on their change of legal status: active and passive administrative acts.

9. Administrative acts can be categorized based on their supplementation requirements: independent and supplementary administrative acts.

10. Administrative acts can be distinguished according to the identity of their administrative relatives: internal and external administrative acts.