This chapter first gives a very high-level description of the major components of function of a computer system. It then motivates the reader by giving reasons why learning assembly language is important for Computer Scientists and Computer Engineers. It then explains why the ARM processor is a good choice for a first assembly language. Next it explains binary data representations, including various integer formats, ASCII, and Unicode. Finally, it describes the memory sections for a typical program during execution. By the end of the chapter, the groundwork has been laid for learning to program in assembly language.