您当前的位置:计算机专业英语28
计算机专业英语28
High-level Programming Languages
  A high-level language is one in which numerous instructions must be executed at the machine language level to perform a function or task specified.一7structions written in a high-level language must be translated into the machine language used by the computer system the program will be executed on The,translator in such a cases the compiler. The high-level language program is known as the source program and the resulting machine language program’s the object program.The compiler is itself a pro-gram .On some computer systems (particularly microcomputers), an interpreter is used instead of a compiler. Interpreters translate the instructions of a source program in a one-by-one manner. As a result, interpreters produce object programs more slowly than compilers.However, interpreters require less memory than compilers.

  High-level languages are sometimes described as being machine independent.This means that program written in a high-level language such as COBOL should run on any computer system ,vital COBOL compiler.In actual practice, however. Several variations have crept into high-level languages so that no high-level language is totally "portable" to all computer systems with a compiler for the language in question. Efforts to standardize high-level languages and compilers have received much attention in recent years。

  High-level languages greatly simplify programming tasks when compared to assembly or machine level languages.Fewer errors are likely to result Programs written in one language may be used another machines with little or no revisions.High-level languages execute slowest and occupy more space in memory than machine or assembly languages, however.
收藏状态
收藏本课程的同学
相关课程