From mainframes to wearable computers

A computer is one of the most brilliant inventions of mankind. Thanks to computer technology, we have been able to achieve storage and processing of huge amounts of data, speed up daily work, carry out critical transactions and achieve precision at work. Depending on the processing power and size of computers, they have been classified under various types. Let us look at the classification of computers.

A mainframe is the most powerful type of computers. It can process and store large amounts of data. It supports multiple users at the same time and can support more simultaneous processes than a PC. The central system is a large server connected to hundreds of terminals over a network. Mainframes are used for large-scale computing purposes in banks, big companies and universities.

A personal computer (PC) is a computer designed for general use by a single person. Personal computers come in different forms such as desktops, workstations, laptops, netbooks, tablet PCs and personal digital assistants. Let us look at each of these types of computers.

A desktop PC has its own processing unit (or CPU), monitor and keyboard. It is used as a personal computer in the home or as a workstation for group work. Typical examples are the IBM PC and the Apple Macintosh. It’s designed to be placed on your desk. Some models have a vertical case called a tower.

A computer that has a more power resources like processing power, memory and additional capabilities to perform special task refers to as workstation. Workstations are often optimized for displaying and manipulating complex data such as 3D mechanical design, engineering simulation results such as for computational fluid dynamics, animation and rendering of images, and mathematical plots.

A laptop (also called a notebook PC) is a lightweight computer that you can transport easily. It can work as fast as a desktop PC, with similar processors, memory capacity, and disk drives, but it is portable and has a smaller screen. Modern notebooks have a TFT (thin film transistor) screen that produces very sharp images. Instead of a mouse, they have a touchpad built into the keyboard – a sensitive pad that you can touch to move the pointer on the screen. They offer a lot of connectivity options: USB (Universal Serial Bus) ports for connecting peripherals, slots for memory cards, etc. They come with battery packs, which let you use the computer when there are no electrical outlets available.

A netbook is a small mobile computing device (a mini laptop) that has less processing power and storage space than a laptop computer. Netbooks are extremely lightweight, and most do not include a CD/DVD drive. However, they support a small keyboard for word processing and other inputs. They have become increasingly popular, particularly among students, bloggers and those who mainly use a laptop to access the Web.

A tablet PC looks like a book, with an LCD screen on which you can write using a special digital pen. You can fold and rotate the screen 180 degrees. Your handwriting can be recognized and converted into editable text. You can also type at the detached keyboard or use voice recognition. It’s mobile and versatile.

A personal digital assistant or PDA is a tiny computer which can be held in one hand. The term PDA refers to a wide variety of hand-held devices, palmtops and pocket PCs. For input, you type at a small keyboard or use a stylus – a special pen used with a touch screen to select items, draw pictures, etc. Some models incorporate handwriting recognition software, which enables a PDA to recognize characters written by hand. Some PDAs recognize spoken words by using voice recognition software. They can be used as mobile phones or as personal organizers for storing notes, reminders and addresses. They also let you access the Internet via wireless technology, without cables.

A wearable computer (Fig. 1.7) runs on batteries and is worn on the user’s body, e.g. on a belt, backpack or vest; it is designed for mobile or hands-free operation. Some devices are equipped with a wireless modem, a small keyboard and a screen; others are voice-activated and can access email or voice mail (adapted from ‘Professional English in Use ICT’). Fig. 1.7. Wearable computer.

1. ______________ – a computer that is smaller in size and has less processing power than laptops, but it is lightweight and portable, has excellent wireless communication capabilities and is less expensive.

2. ______________ – a small computer that fits into your clothes.

3. ______________ – a hand-held computer which can be used as a mobile phone, a web browser, message recorder or a personal organizer.

4. ______________ – a portable computer that can be closed up like a briefcase, but it can be as powerful as a desktop PC.

5. ______________ – a large computer used for intensive data processing and often linked to many terminals.

6. ______________ – a high quality computer, typically with lots RAM, plenty of CPU power and a high quality video card.

7. ______________ – a popular computer for home use and can be found in many businesses.

8. ______________ – a portable computer capable of advanced handwriting recognition via use of a stylus or on-screen keyboard.

Exercise 50. Decide if these statements are True or False.

1. Laptops are as compact as desktop PCs but have different software.

2. Workstations are similar to desktop PCs and have greater memory and more extensive mathematical abilities.

3. A netbook is a small notebook with less powerful components meant for surfing the web, reading email and other basic tasks.

4. Mainframes have less memory, speed and capabilities than workstations.

5. A desktop PC is a multi-user computer that often contains complex arrays of processors.

Listening

Exercise 51. (Track 1.4). Listen to the short lecture by an expert on computer systems. As you listen, fill in the blanks in the text.

Дата добавления: 2015-11-14