Data Representation

Question 1

Data

Answer 1

collection facts, symbols, or measurements. There is no significance

Data is collected and processed to create information for making decisions

Question 2

Information

Answer 2

result of processing, manipulating, organizing data that adds to a person’s knowledge

Question 3

Data encoding

Answer 3

process of transferring data into a digital format that can be stored or processed in computers

Question 4

Data decoding

Answer 4

reverse of encoding, transferring data from a digital format into a form that humans can understand

Data > Encoding > (bits) 0100…1000 > Decoding > Data

Question 5

Character encoding

Answer 5

representing characters used in the world’s writing systems as bits for transmission, processing, or storage of textual data

Question 6

Character maps

Answer 6

table that matches each character with a unique combination of bits

Question 7

ASCII

Answer 7

American Standard Code for Information Interchange is a character-encoding scheme
7-bit character code to encode 128 characters (including 33 non-printing)
Extra bit in a byte is used as a parity bit

Question 8

Extended ASCII

Answer 8

uses a byte to encode characters including standard ASCII and additional 127 characters such as %, $, &

Question 9

Unicode

Answer 9

standard designed to encode text and symbols from all the world’s alphabets. It includes more than 110,000 characters

Question 10

UTF-8

Answer 10

: A variable-width encoding with 8-bit, 16-bit, 24-bit, or 32-bit. Compatible with ASCII and picks width depending on character to minimize storage

Question 11

UTF-32

Answer 11

: encodes exactly 32 bits per character. Main advantage is that characters are directly mapped to bits without any operation therefore, characters are encoded and decoded efficiently. However, method requires larger storage

Question 12

UTF-16:

Answer 12

variable-width encoding with 16-bit or 32-bit representation between UTF-8 and UTF-32

UTF-8 is used in web
UTF-16 is used in Java and Windows
UTF-8 and UTF-32 is used in Unix systems
Conversions between standards are possible and makes it easier to support multiple input and output formats

Question 13

Data types::

Answer 13

Numerical: includes all numbers (integer, real)

Question 14

Text (Alpha-numerical): includes any combination of characters (numbers, letters, special characters)

Answer 14

Data types are functioned (1) to define the possible values that the data can have, (2) to define the operations that can be performed on the data, (3) to determine the storage requirement of the data
Helps organize data in storage medium (computer memory or hard drive)

Question 15

Metadata

Answer 15

data dictionary that describes the structure of the actual data

Question 16

bit=(BInary digiT)

Answer 16

Smallest piece of information

Question 17

Byte

Answer 17

A collection of 8 bits
• A byte is commonly used as a unit of
storage measurement in computers.

01010101 : 8bits = 1byte

Question 18

The average score for the test is 72.1

Information
Data

Answer 18

Information

Question 19

Data types #2

Answer 19

TINYINT= max 127

SMALLINT = 255

MEDIUMINT= 32767

INT= 65535

FLOAT=

DOUBLE=

CHAR(n)=

TEXT=

Question 20

Test scores are: 31, 90, 45, 86,…

Data
Information

Answer 20

Data

Question 21

July is usually dry in the US

Data
Information

Answer 21

Information

Question 22

New York is the largest US city

Information
Data

Answer 22

Information

Question 23

It is raining..

Data
Information

Answer 23

Data