Operating Systems: Hidden Software

When a brand new computer comes off the factory assembly line, it can do nothing. The hardware needs software to make it work. Are we talking about applications software such as word processing or spreadsheet software? Partly. But an applications software package does not communicate directly with the hardware. Between the applications software and the hardware is a software interface - an operating system. An operating system is a set of programs that lies between applications software and the computer hardware.

The most important program in the operating system, the program that manages the operating system, is the supervisor program, most of which remains in memory and is thus referred to as resident. The supervisor controls the entire operating system and loads into memory other operating system programs (called nonresident) from disk storage only as needed.

An operating system has three main functions: (1) manage the computer's resources, such as the central processing unit, memory, disk drives, and printers, (2) establish a user interface, and (3) execute and provide services for applications software. Keep in mind, however, that much of the work of an operating system is hidden from the user. In particular, the first listed function, managing the computer's resources, is taken care of without the user being aware of the details. Furthermore, all input and output operations, although invoked by an applications program, are actually carried out by the operating system.

Task  5. Complete the gaps in this summary of the text on operating systems using these linking words and phrases:

although  in addition

because   such as

but therefore

The user is aware of the effects of different applications programs…………operating systems are invisible to most users. They lie between applications programs, …………. word-processing, and ……………… the hardware. The supervisor program is the most important. It remains in memory, it is referred to as resident. Others are called non-resident they are loaded into memory only when needed. Operating systems manage the computer’s resources,………………….the central processing unit    …………….. they   establish a

user interface, and execute and provide services for applications software ………… input and output operations are invoked by applications programs, they are carried out by the operating system.

LESSON 13

What Is It?

Task  1. Read and translate the text:

Задание 1. Прочитайте и переведите текст:

Imagine a room filled with many spiders, each spinning its own web. The webs are so interconnected that the spiders can travel freely within this maze. You now have a simplified view of the Internet — a global collection of many different types of computers and computer networks that are linked together. Just as a telephone enables you to talk to someone on the other side of the earth who also has a phone, the Internet enables a person to sit at his computer and exchange information with other computers and computer users any place in the world. Some refer to the Internet as the information superhighway. Just as a road allows travel through different areas of a country, so the Internet allows information to flow through many different interconnected computer networks. As messages travel, each network that is reached contains information that assists in connecting to the adjacent network. The final destination may be in a different city or country. Each network can "speak" with its neighbor network by means of a common set of rules created by the Internet designers. How many networks are connected worldwide? Some estimates say over 30,000. According to recent surveys, these networks connect over 10,000,000 computers and some 30,000,000 users throughout the world. It is estimated that the number of connected computers is doubling each year. What can people locate on the Internet? It offers a rapidly growing collection of information, with topics ranging from medicine to science and technology. It features exhaustive material on the arts as well as research material for students and coverage of recreation, entertainment, sports, shopping, and employment opportunities. The Internet provides access to almanacs, dictionaries, encyclopedias, and maps. There are, however, some disturbing aspects to consider. Can everything on the Internet be regarded as wholesome? What services and resources does the Internet offer? What precautions are in order?

Task  2. Answer the following questions:

Задание 2. Ответьте на следующие вопросы:

1. Some people think that the Internet is very harmful, especially for young people, because it carries a lot of information about sex, drugs, violence and terrorism. Do you think that some kind of censorship is necessary on the WWW?

2. World famous authors and publishers say that the Internet violates their copyright because Web-programmers put all kinds of books, pictures, music, films and programs free on the Internet and this reduces their sales and profits.

Task  3. Has anyone in your group experience working on the Internet? Ask them

1) about the difficulties they had;

2) useful information retrieved;

 3) fun they got?

Why so few people have experience working on the Internet?

Task  4. Read the text “What Is it?” and discuss the following questions in group:

Задание 4. Прочитайте текст и обсудите следующие вопросы в группе.

a) To what spheres of human’s activities does the Internet provide access to?

b) What services and resources does the Internet offer?

Task 5. Complete these sentences with the correct form of the verb:

infinitive or -ing form.

Don’t switch off without (close down) your PC.

I want to (upgrade) my computer.

He can’t get used to (log on) with a password.

You can find information on the Internet by (use) a search engine

He objected to (pay) expensive telephone calls for Internet access.

He tried to (hack into) the system without (know) the password.

You needn’t learn how to (program) in HTML before (design) webpages.

I look forward to (input) data by voice instead of (use) a keyboard.

Task 6. Try to find the commands from the lists below which will have these actions.

VMS - help, directory, search, copy,  rename, print, show users, showtime,  create/directory grep phone .                     

Unix – write, cp, ipr, is, mkdir, date, rm, man, rwho

LESSON 14