Perception, affection and consciousness are basic psychological functions of human being. Affection is the subjective reflection of different kinds of objects. The foundation of human being's thinking is constituted by the three basic functions. Affective computing is an effective tool of revealing the affectiveness of human being in order to understand the world. Our research of affective computing focused on the relation, the generation and the influent factors among different affections. In this paper, the affective mechanism, the basic theory of affective computing, is studied, the method of acquiring and recognition of affective information is discussed, and the application of affective computing is summarized as well, in order to attract more researchers into this working area.