18. Ответьте на вопросы:

1. What functions can the systems software perform?

2. What is the difference between the primary memory and virtual memory?

3. What tasks are modern systems programs for large computers capable of carrying out?

4. Where can the UNIX operating system be used?

19. Прочтите и переведите текст.

TEXT C

APPLICATIONS SOFTWARE

Applications software includes most of the types of programs we use every day to get our computerized work done. Applications programs are widely used in our society for entering and editing text (word processing and desktop publishing programs), for entering and manipulating numeric data (spreadsheets and many other business programs), and for record keeping (database management programs). These types of programs are sometimes referred to as general-purpose applications. Because they are used by a wide variety of users in many different environments, they are also known as horizontal applications.

There are only a few types of software that can be truly said to cut across all aspects of computerized activity. They are:

Word processing and desktop publishing

Electronic spreadsheets

Database management

Graphics

Communications

These programs are used by many different types of users for many different purposes. But there are also much more specialized applications programs. They are used for such computer tasks as the calculation of the wind currents around a skyscraper, for analysing the chemical components in an ore sample, or for teaching a child how to tell time. An almost endless variety of such programs are sometimes referred to as vertical applications because, even though they are also examples of the applications category, they are used to carry out tasks within a narrowly defined area.

Because both horizontal and vertical applications are used as tools to help us get our work done, they are all sometimes referred to as productivity software.

Most of the applications programs that were created during the early computer generations were used for business-related activities. However, as these companies continued to develop programs for in-house use, certain applications began to emerge that solved the types of data-processing problems that were common to a variety of organizations. As computers spread throughout the business community, programmers began to sell their most popular applications programs to other businesses. Eventually, as the demand grew, the manufacturer and sale of applications programs became a business in and of itself.

But it took the development of the microcomputer to turn this smattering of software sales into a significant software business. At first, personal computers were used mainly by hobbyists who built and programmed their own computers. As more and more people bought their own PCs, there was soon a growing demand for programs that could help individual users get their work done. They wanted to keep track of their stamp collection, or to balance their checking accounts. While the big businesses that used big computers used only a narrow range of business-oriented application programs, the needs of the PC world were as varied as the types of users.

Generally, it was not the professional programmers who worked for big businesses who created the programs to meet this new demand; it was more likely to be the users of the PCs themselves. As personal computers became much more popular in the early 1980s, many books were written about how to program them. This created a new crop of PC programmers who started to create new types of programs to meet the growing need. They created new, easier-to-use word processing programs. They devised easier ways to create computerized record keeping and report-generating forms. In fact, the changing needs of personal computer users resulted in the creation of entirely new types of programs. For example, many credit the rapid growth of the PC business itself to the creation of computerized spreadsheets that could be used to enter and analyse information based on numbers.