SUMMARY
The article deals with some aspects of the process of forming the future computer science bachelor's graphic competency at the stage of user's interface prototyping in the course of software development. The modern situation has been studied and the urgency of the stage of user's interface prototyping as a mediator in the man-machine coordination during the process of software development is proved. The Conceptual set in the sphere of prototyping is examined, namely — the concepts of wireframe, prototype and mockup. The factors of projects successfulness, the problems in the coordination of the project participants and the methods of their overcoming are being considered. The comparison of the essence and the analysis and the main methods of prototyping and correlating their value during the software development are given. The comparative analysis of the software and on-line resources for prototyping according to the detalization degree and taking into account the basic characteristics of a means, types and stages of prototyping, portability and using the means is carried out. The necessary base of knowledge, skills and knacks, forming during the study of such disciplines as “Computer Graphics” and “The Essential of Computer Design”, as well as essentials of composition, colour theory, ergonomics and typography is determined. The necessity of both the student's mastering an amount of theoretical knowledge and its successful using in his practical activity is stressed. The results of the research can be a substratum for improving the content of the educational and methodical complex in the discipline “Software Projecting” for computer science bachelors by means of introducing the teaching of prototyping from the low-fidelity to high fidelity detalization. The influence of user's interface prototyping on the formation of the future computer science bachelor's professional qualities is determined.