1.2 memory and storage

Question 1

primary storage

Answer 1

compromised of RAM and ROM. it holds data and instructions that the CPU can access more quickly and easily than from secondary storage devices

Question 2

RAM - random access memory

Answer 2

it is volatile (data is lost when the computer is powered off)
-purpose: temporary storage of currently executing instructions and data

Question 3

Virtual Memeory

Answer 3

using part of the hard disk as if it were random-access memory. Allows more applications to be open than physical memory can holds

Question 4

secondary storage

Answer 4

permanent storage of instructions and data not currently in use by the processor. Stores the operating system, applications and data. read-and-write and non-volatile

Question 5

optical storage

Answer 5

CD-R, CD-RW, DVD-R, DVD-RW
-Used for music films and archive files
-low capacity, slow access speed, high portability, prone to scratches and low cost

Question 6

solid-state storage

Answer 6

memory cards and solid-state hard drives (SSD).
used for digital cameras and smartphones
-medium capacity
-high portability
reliable and durable
no moving parts
fast data access speed
high cost

Question 7

magnetic storage

Answer 7

hard disk drive
-used for operating system and applications
-high capacity
-medium data access speed
low portability (except for portable drives)
reliable but not durable
medium cost

Question 8

storage capacity

Answer 8

the amount of data a storage device can store

Question 9

storage speed

Answer 9

the read/write access speed of a storage device

Question 10

storage portability

Answer 10

how easy it is to transport a storage device

Question 11

storage durability

Answer 11

how resistant a storage device is to damage and wear

Question 12

storage reliability

Answer 12

a relative measure of confidence that a storage device will function correctly and allow you to read, write and modify data

Question 13

storage cost

Answer 13

the relative price of a storage device - e.g. per megabyte of data

Question 14

bit

Answer 14

the smallest unit of storage, represented by either a binary 1 or 0

Question 15

nibble

Answer 15

half a byte. Four bits

Question 16

byte

Answer 16

a collection of eight bits

Question 17

kilobyte

Answer 17

one kilobyte (KB) is 1024 bytes. For purpose of calculations in an exam, you can treat a kilobyte as 1000 bytes

Question 18

denary numbers

Answer 18

a numerical system of notation that uses 10 as its base. The ten decimal base digits 0-9

Question 19

binary numbers

Answer 19

binary describes a numbering scheme with only two possible value for each digit 0 and 1

Question 20

binary arithmetic

Answer 20

the process of adding two or more positive 9-bit binary numbers (0-255)

Question 21

overflow

Answer 21

the generation of a number that is too large to be represented by the device intended to store it

Question 22

hexadecimal

Answer 22

a numerical system of notation that uses 16 rather than 10 as its base. 0-9 and A-F

Question 23

binary shifts

Answer 23

allows you to easily multiply or divide a base-2 binary number. Left shift multiplies by 2, right shift divides by 2

Question 24

character set

Answer 24

a set of symbols represented by computer.

Question 25

ASCII

Answer 25

-America Standard Code for Information Interchange -a character set devised for early telecommunication systems but proved to be ideal for computer systems

Question 26

Unicode

Answer 26

standard character set that replaces the use of multiple different character sets. Incorporates characters from almost all global languages. A 16-bit extension of ASCII

Question 27

pixels

Answer 27

the smallest unit of a digital image or graphic that can be displayed on a digital device. A pixel is represented by a dot or square on a computer display

Question 28

Metadata

Answer 28

a collection of data that describe and provides information about other data

Question 29

colour depth

Answer 29

-also known as bit depth. -either the number of bits used to indicate the colour of a single pixel in a bitmap image or video frame buffer or each colour component of a single pixel

Question 30

resolution

Answer 30

the number of pixels in a display, expressed in terms of the number of pixels on the horizontal and vertical axes

Question 31

image quality

Answer 31

the overall detail of an image, affected by colour depth and resolution

Question 32

image file size

Answer 32

the total size of an image file in storage

Question 33

sample rate

Answer 33

the number of samples taken per second, measured in hertz (Hz)

Question 34

sample duration

Answer 34

how many seconds of audio a sound file contains

Question 35

sample bit depth

Answer 35

the number of bits available to store each sample (e.g. 16-bit)

Question 36

playback quality

Answer 36

-the finished quality of the digital sound file. -this affected by the sample rate and bit depth -the higher the number, the better the quality

Question 37

sound file size

Answer 37

the total size of a sound file in storage

Question 38

compression

Answer 38

the process of reducing the size of a file

Question 39

lossy compression

Answer 39

a compression method that generally involves a loss of quality where generally it will be noticed

Question 40

lossless compression

Answer 40

a compression method that allows a file to be recreated in its original quality