The subject of the present thesis is graphics protocols. However, related to the graphics protocols areas of computer graphics and computer networks are discussed. The six chapters of the thesis include the following: The first chapter gives a brief introduction to the data communication and computer networks, discusses protocols in general and presents some examples of networks and protocols. Finally, discusses how computer graphics is implemented over a computer network. The second chapter deals with graphical output. Requirements of graphical output, typical output devices and graphics packages are pointed out. Also the device independence of graphical output is discussed and an example in using graphical primitives is presented. The third chapter deals with the problems of graphical output transmission. The protocols used for such transmission and the format of graphical output are discussed as well as the requirements for terminal intelligence. Also the importance for standardisation of graphical output is pointed out. The fourth chapter discusses the interactive aspect of computer graphics Typical hardware for graphical input is presented and the interactive capabilities of various graphics packages are mentioned. Also, a brief discussion of device independent graphical input appears. Finally, command languages for driving graphical application programme are discussed and the fact that a command language for a specific application constitutes an inter active protocol between the user and the system is pointed out. The fifth chapter deals with interactive graphics in a network environment. Requirements such as response times and band- widths are discussed. Host-satellite systems and general distributed networks are presented and graphics protocols implemented over both environments are discussed. Finally, the sixth chapter is the conclusion of the thesis. In it the main points of the work are emphasized and future trends for research and developement are pointed out.