Reading Comprehension Practice

Programming languages

There are literally hundreds of high-level languages, each one having strengths and weaknesses for any particular application. The language COBOL (Common Business Oriented Language), for example, was designed for business applications. It is very useful at handling large amounts of stored information and can be used to design complex forms and reports. FORTRAN (FORmula TRANslation) is one of the oldest high-level languages. FORTRAN makes complex calculations easy to perform but is not very good at manipulating records or formatting output reports. In the educational environment, the most popular languages for microcomputers are BASIC and PASCAL, while each mainframe system has its own specialized language.

All programming languages have advantages and disadvantages. All are very flexible; most things that you want done can be programmed. However, since they also require complete specification of every detail, programming languages can be difficult to use. Programming errors are common, and it often takes a great deal of time to write a completely functional and problem-free program.

Increasingly popular in education is a special type of high-level language: the authoring system. It differs from a programming language in that you can use it to create a program without using any programming commands. Most authoring systems have a similar format: as you use the system you are constantly prompted about what options are available. For instance, the system may first ask whether you wanted to enter information or questions. Depending on the option you choose, you are taken to a display where you enter either the information or the questions, just as you would on the typewriter. That is, the words you type and their position on the screen are the same as they would appear in the final program. No commands are necessary.

If the computer needs more information at any point, the system requests this through a series of simple questions. For example, the system may ask how many attempts you will allow when answering the question, what is the correct answer, whether other answers are acceptable, or what hints to give. The authoring system conducts a dialogue: it asks questions, and you respond. Your answers provide all the additional information the system needs to construct the final program. It takes what you have entered and, on its own, writes the program to produce the desired results.

Authoring systems, like PASS, represent major advances in the field, even though they often impose many constraints on the author. Compared to a programming language, most present-day authoring systems are not very flexible and force the program to conform to a relatively small number of alternatives. Not surprisingly, then, most programs developed on an authoring system look very much alike. However, because authoring systems are easy to use, require no knowledge of a programming language, and save time in producing a final product, we believe that authoring systems have an important future.

Read the text and discuss the following:

Date: 2015-12-11; view: 1040