Page 215 - DCAP104_EXPOSURE_TO_COMPUTER_DISCPLINES

Exposure to Computer Disciplines

Notes
11.5 Summary

11.6 Keywords
11.7 Self-Assessment Questions
11.8 Review Questions
11.9 Further Reading

Objectives

After studying this unit, you will be able to:

• Understand the categories of computer language.
• Discussed machine and assembly language.
• Explained high level languages.
• Understand the www development language.

Introduction

A programming language is an artificial language designed to express computations that can
be performed by a machine, particularly a computer. Programming languages can be used to
create programs that control the behavior of a machine, to express algorithms precisely, or as
a mode of human communication. The earliest programming languages predate the invention
of the computer, and were used to direct the behavior of machines such as Jacquard looms and
player pianos. Thousands of different programming languages have been created, mainly in the
computer field, with many more being created every year. Most programming languages describe
computation in an imperative style, i.e., as a sequence of commands, although some languages,
such as those that support functional programming or logic programming, use alternative forms of
description. A programming language is usually split into the two components of syntax (form) and
semantics (meaning) and many programming languages have some kind of written specification
of their syntax and/or semantics. Some languages are defined by a specification document, for
example, the C programming language is specified by an ISO Standard, while other languages,
such as Perl, have a dominant implementation that is used as a reference.

11.1 Categories of Programming Language

There are literally thousands of programming languages in the world and each has its own
strengths and weakness. Many are simply for teaching or language research. These languages
do not interest or concern me. They are frequently limited and almost useless. There is a certain
set of programming fields/categories that I believe are currently distinct enough to have an
independent programming language to represent them. Each is however, narrow enough that
there is no need for more than one language.
Language Role Best Candidate

Scripting
Programmer’s scripting Better Scheme (+OO)

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