1.4.1 Data Types

Question 1

What is an integer?

Answer 1

A whole number
Can be positive or negative

Question 2

What is a real?

Answer 2

Positive or negative number
Can have fractional part

Question 3

What is a character?

Answer 3

A single symbol
Includes letters, numbers & symbols

Question 4

What is a string?

Answer 4

A group of characters
Can store one or more characters

Question 5

What is Boolean?

Answer 5

True or False

Question 6

What is a bit?

Answer 6

A single binary digit

Question 7

What is a byte?

Answer 7

Eight binary digits

Question 8

What is a nybble?

Answer 8

Four binary digits

Question 9

Which bit is the least significant?

Answer 9

The furthest to the right

Question 10

Which bit is the most significant?

Answer 10

The furthest to the left

Question 11

What is Sign Magnitude?

Answer 11

The equivalent of adding a + or - sign in front of a number

Question 12

How is a negative number represented using Sign Magnitude?

Answer 12

By adding a leading 1

Question 13

How is a positive number represented using Sign Magnitude?

Answer 13

By adding a leading 0

Question 14

Describe how a number can be put into two’s complement.

Answer 14

Flipping the bits of positive number
Adding one

Question 15

How is binary subtraction performed?

Answer 15

Using binary addition with a negative two’s complement number

Question 16

What base is hexadecimal?

Answer 16

16

Question 17

What characters are represented by 10-15 in hexadecimal?

Answer 17

A-F

Question 18

What is floating point binary?

Answer 18

Binary numbers with a mantissa & exponent

Question 19

Where is the binary point in the mantissa of floating point binary?

Answer 19

After the most significant bit

Question 20

How is floating point binary converted into denary?

Answer 20

Exponent converted to denary
Binary point of mantissa moved according to exponent

Question 21

What is the benefit of floating point binary?

Answer 21

Increased precision
Larger range of numbers can be stored

Question 22

What is meant by normalised floating point binary?

Answer 22

Mantissa starts 01 for positive number
Mantissa 10 for negative number

Question 23

Describe how addition can be performed with two floating point binary numbers.

Answer 23

Both exponents the same
Add mantissas
Normalise result if required

Question 24

Describe how subtraction can be performed with two floating point binary numbers.

Answer 24

Both exponents the same
Mantissa of number to be subtracted converted to two’s complement
Binary addition carried out
Normalise result if required

Question 25

What is a logical shift?

Answer 25

Involves moving all of the bits in a binary number of a specified number of places to the right/left

Question 26

What is the result of a logical shift left?

Answer 26

Multiplication

Question 27

What is the result of a logical shift right?

Answer 27

Division

Question 28

What is the effect of a logical shift left by one place?

Answer 28

Initial number doubled

Question 29

What is the effect of a logical shift right by one place?

Answer 29

Initial number halved

Question 30

How are masks applied to binary numbers?

Answer 30

By combining them with logic gate

Question 31

What is a character set?

Answer 31

A set of characters that can be represented by a computer

Question 32

How many bits does ASCII use?

Answer 32

7 bits

Question 33

Whats the maximum number of characters represented by ASCII?

Answer 33

128 characters

Question 34

What is the drawback of ASCII?

Answer 34

Limited character set

Question 35

How many bits does Unicode use?

Answer 35

Varying amount