Assembly language is a symbolic representation of a computer’s binary machine code (machine language). Humans have great difficulty understanding and manipulating these binary values. Instead, we prefer to work with symbols and words instead of long sequences of digits. Assembly language is more readable than machine code because it uses symbols and words instead of bits, which makes it more suitable for humans. Each processor is designed for a specific set of binary instructions or instruction set architecture (ISA). Thus, each ISA has its own assembly language. No two assembly languages are the same.

Programmers today do not commonly write programs using assembly language. Its use is typically limited to special purposes such as device drivers or embedded systems where speed or code size is critical. Computer scientists who design and build compilers and hardware, however, must understand and work at the assembly language level. Computer scientists in general can greatly benefit from the knowledge of how structured high-level language instructions are implemented in assembly language. In this chapter, we introduce assembly languages in general and begin our exploration of the MIPS assembly language.

• Introduction
• Integer Arithmetic
• Pseudo Instructions
• Instruction Encodings