TEXT № 5. Computer Memory

TASK: Read and translate the following text. Learn the vocabulary by heart. Point out the main idea of the text. Can you add something new about the computer memory?

To process information electronically, data are stored in a computer in the form of binary digits, or bits, each having two possible representations (0 or 1). If a second bit is added to a single bit of information, the number of representations is doubled, resulting in four possible combinations: 00, 01, 10, or 11. A third bit added to this two-bit representation again doubles the number of combinations, resulting in eight possibilities: 000, 001, 010, 011, 100, 101, 110, or 111. Each time a bit is added, the number of possible patterns is doubled. Eight bits is called a byte; a byte has 256 possible combinations of 0s and 1s.

A byte is a useful quantity in which to store information because it provides enough possible patterns to represent the entire alphabet, in lower and upper cases, as well as numeric digits, punctuation marks, and several character-sized graphics symbols, including non-English characters such as π. А byte also can be interpreted as a pattern that represents a number between 0 and 255. A kilobyte— 1, 024 bytes—can store about 1, 000 characters; a megabyte can store about 1 million characters; a gigabyte can store about 1 billion characters; and a terabyte can store about 1 trillion characters.

The physical memory of a computer is either random access memory (RAM), which can be read or changed by the user or computer, or read-only memory (ROM), which can be read by the computer but not altered. One way to stone memory is within the circuitry of the computer, usually in tiny computer chips that hold millions of bytes of information. The memory within these computer chips is RAM. Memory also can be stored outside the circuitry of the computer on external storage devices, such as magnetic floppy disks, which can store about 2 megabytes of information; hard drives, which can store thousands of megabytes of information; CD-ROMs (compact discs), which can store up to 630 megabytes of information; and DVDs (digital video discs), which can store 8.5 gigabytes of information. A single CD-ROM can store nearly as much information as 700 floppy disks can, and a DVD can hold 15 times as much data as a CD-ROM. (2151)

Vocabulary:

memory – память

to process – обрабатывать

binary – двойной, бинарный, двоичный

digit – цифра, число

representation – изображение

to interpret – объяснить, перевести

pattern – образец, модель

character – знак, символ

random access memory (RAM) – оперативное запоминающее устройство (ОЗУ)

chip – микросхема

storage device – запоминающее устройство

external – внешний

floppy disk – гибкий магнитный диск, дискета

hard drive – жесткий диск