5 Семестр
Unit 9
Computer technology
Text 9.1
Read and translate the text.
A computer is an electronic device that performs high-speed mathematical or logical operations and executes instructions in a program. Its main functions are to accept and process data to produce results, store information and programs and show results.
The main characteristics of these powerful machines are:
■ speed, as they can execute billions of operations per second
■ high reliability in the elaboration and delivery of data
■ storage of huge amounts of information
A computer consists of hardware and software. The word hardware refers to all the components you can physically see such as the CPU (Central Processing Unit), the internal memory system, the mass storage system, the peripherals (input and output devices) and the connecting system. Software, instead, comprises all the computer programs and related data that provide the instructions for a computer to work properly.
The CPU is the brains of your computer and consists of ALU (Arithmetic Logic Unit), which carries out the instructions of a program to perform arithmetical and logical operations, and CU (Control Unit), which controls the system and coordinates all the operations. In order to memorise input and output data, there is an internal memory that can be distinguished into volatile and non-volatile. Volatile memory is memory that loses its contents when the computer or hardware device is off. Computer RAM (Random Access Memory) is a good example of volatile memory. It is the main memory of the computer where all data can be stored as long as the machine is on. On the contrary, a non-volatile memory contains information, data and programs that cannot be modified, or can be modified only very slowly and with difficulty. Computer ROM (Read Only Memory), for example, contains essential and permanent information and software which allow the computer to work properly. Memory storage devices are available in different options, sizes and capacities. These devices are extremely useful; they can be rewritten and offer incredible storage capacity, up to 256 GB. They can be magnetic (hard disks), optical (CDs and DVDs) or solid (flash memory cards).
Complete the table.
-
Component (acronym)
Full name/Description
Functions and properties
hardware
software
CHU
ALU
CU
RAM
ROM
Text 9.2
Read and translate the text.
Mass storage devices are available in an incredible number of options with different storage capacity up to 256 GB for some portable drives. A very popular type of removable device is represented by USB flash drives, which are much smaller and lighter than other portable drives, but which can still provide a huge storage capacity
A USB flash drive is a flash memory data storage device integrated with a USB (Universal Serial Bus) interface. USB flash drives are removable and rewritable, and they’re small enough to be carried in a pocket. These portable drives are faster, have thousands of times more capacity, and are more durable and reliable than CD-ROMs because of their lack of moving parts.
Unlike most removable drives, a USB drive does not require rebooting after it’s attached, they are very robust and use very little power. They just need to be plugged into a USB port to work and they’re compatible with any modern operating system, such as Linux, Mac OS X and Windows.
A flash drive consists of a small printed circuit board carrying the circuit elements and a USB connector, insulated electrically and protected inside a plastic case.
The drive is often used as a backup medium to save data, because it is very user-friendly and it can be carried off-site for safety despite being large enough for several backups. Moreover, flash drives are cheaper and less fragile than many other backup systems. Its only disadvantage is that it can be easily lost because of its size and it’s easy for people without a right to data to take illicit backups.
Some specially manufactured flash drives are provided with a metal or rubber case designed to be waterproof and almost unbreakable. It’s been tested that these flash drives can retain their memory even after being submerged in water, put in a washing machine and run over with a car..
Find the synonyms for the following words in the text.
long-lasting:
sturdy:
inserted:
easy to use:
fabricated:
hold:
Read the text again and decide if the following statements are true (T) or false (F), then correct the false ones.
1 Flash drives are provided with a very limited storage capacity.
2 They are lighter that other removable drives.
3 They need an external power supply to work.
4 USB flash drives are compatible with few operating systems.
5 A plastic case prevents the printed circuit board from being damaged.
6 USB drives are convenient for transferring data between computers or for personal backups.
7 They are more expensive than other backup systems.
8 Some models continue to work even after being accidentally dropped into water
Text 9.3
Read and translate the text.
We call hardware the equipment involved in the functioning of a computer. It consists of several components that can either send data to the computer (input devices) or convert and transfer data out of the computer in the form of text, sound, image, or other media (output devices). The main input and output devices are:
Monitor: this is the display, which helps you control computer operations. It accepts video signals from a computer and shows information on a screen. The first models used cathode ray tubes (CRTs), which was the dominant technology until they were replaced by liquid crystal displays (LCDs) in the 21st Century.
Keyboard: this is like a typewriter with an arrangement of keys corresponding to written symbols. It is generally used to type text and numbers in a word processor. However there are some special keys or combination of keys which, pressed simultaneously, can produce actions or computer commands.
Mouse: this is a dynamic pointing device used to move the cursor on the screen. It consists of a plastic case, a little ball that sends impulses to the computer when rolled on a flat surface, one or more buttons, and a cable that connects the device to the computer. Modern computers are provided with built-in pointing devices that let you control the cursor by simply moving your finger over a pad.
Scanner: this captures images from printed pages or photos and converts them into digital data. They usually come with software that lets you resize or modify a captured image.
Printer: this receives text and graphics from a computer and transfers the information to paper. It may vary in size, speed, sophistication, and cost. In general, more expensive models are used for higher-resolution colour printing.
Speaker: this converts electrical signals into sounds and allows you to listen to music, multimedia web sites and conversations with other people.
Modem: this is a device or program that enables a computer to transmit data over telephone lines, by converting digital signals into analog waves. It can be either internal or external to your computer.
Disk drives: these are devices that allow you to read and write data on disks. They can be either mounted inside the computer and store the computer operating system and all the documents and programs, or come in the form of removable devices.
Read and translate the text.
When you go to a computer shop, you can find computers for any use, size or capability.
1 Desktop: this is a personal computer intended for regular use at a single location. It’s designed to sit on your desk, and as such it consists of a monitor and a tower with extra drives inside.
2 Laptop: this is a portable computer, which integrates all the usual components of a desktop computer into a single unit. Smaller versions of laptops are known as notebooks. It is useful for people who do not have a fixed place to work at. They are lighter and handier than desktop computers, but they also tend to be more expensive. They require an expensive battery that needs to be recharged quite often.
3 Netbook: this is a portable computer, with limited capabilities as compared to standard laptops. It is smaller and lighter, but it also has less processing power than a full-sized laptop. It is useful for people who don’t have a fixed place to work at or for those who travel, but still need to surf the Net. They use a battery which needs to be recharged often.
4 Palmtop: this is a small portable computer designed to have large amounts of information close to hand. They are provided with light long- lasting batteries and special operating systems. They don’t require any keyboard but use special pens or touch screens to enter data and access information.
5 Mainframe: this is a very large and expensive computer capable of supporting thousands of users at the same time. For this reason, it is used in businesses and it’s the centre of computer networks. These super computers, which are usually as big as a large refrigerator, are the most powerful and expensive ones and they’re used for jobs which require enormous amounts of calculations, such as weather forecasting, engineering design and economic data processing.
Answer the questions.
1 What does a desktop computer consist of?
2 Are desktop computers designed to be carried around?
3 Who are laptops useful for?
4 What is the difference between a netbook and a laptop?
5 How can you access or enter information on a palmtop?
6 What are mainframes used for?
Text 9.4