Chapter 9 - Programming Languages

Abstract

Each computer can only understand the programs that are written in its own machine language. Machine languages are machine dependent because they are so closely related to the structure of a particular machine. Most programs are written in assembly languages or high-level languages. Assembler programs translate assembly language programs into machine language programs. Assembly language programs can be written faster, have fewer bugs, and are easier to understand and modify than machine language programs. Macro instructions are single statements that an assembler expands into several assembly language statements. High-level languages use English phrases and common mathematical notations. They can convey in one statement what might take many statements in machine and assembly languages. High-level languages are easier to learn than assembly languages. High-level languages are categorized as either procedure oriented or problem oriented. In program development environments, “quick-and-dirty” compilers are used. These translate programs quickly, although the resulting machine language programs might not run as efficiently as possible.