1.4.1 - data types

Question 1

primitive data type

Answer 1

One which is provided by a programming language.
e.g., integer, real, string

Question 2

overflow error

Answer 2

occurs where a carry from the most significant bit requires a
ninth bit

Question 3

2 methods to represent negative numbers in binary

Answer 3

• sign and magnitude
• two’s complement

Question 4

bit

Answer 4

The fundamental unit of information in the form of either a single 1 or 0.

Question 5

kibibyte (KiB)

Answer 5

1024 bytes

Question 6

full form of ASCII

Answer 6

American standard code for information interchange

Question 7

ASCII

Answer 7

• originally 7 bits
• now 8 bits

Question 8

What do the first 32 codes of ASCII represent?

Answer 8

non-printing characters used for control such as backspace

Question 9

unicode

Answer 9

• originally (UTF-16)
• now, (UTF-32)

Question 10

How was compatibility retained between Unicode and ASCII?

Answer 10

The first 128 codes in Unicode were the same as ASCII.

Question 11

0+0

Answer 11

0

Question 12

0+1

Answer 12

1

Question 13

1+1

Answer 13

0 carry 1

Question 14

1+1+1

Answer 14

1 carry 1

Question 15

overflow errors

Answer 15

Where a carry from the most significant bit requires a
ninth bit.

Question 16

sign and magnitude

Answer 16

• change the MSB to 0 if positive
• change the MSB TO 1 if negative

Question 17

MSB

Answer 17

most significant bit

Question 18

two’s complement

Answer 18

• copy out positive binary upto and including the first 1
• flip the rest

Question 19

normalisation

Answer 19

The process of moving the binary point of a floating point number to provide the
maximum level of precision for a given number of bits.

Question 20

How can we identify a normalised number?

Answer 20

• positive number start with 01
• negative numbers start with 10

Question 21

arithmetic shift

Answer 21

It takes into account the sign bit, which always remains the same.

Question 22

NOT

Answer 22

flip all the bits

Question 23

AND

Answer 23

both have to be 1

Question 24

OR

Answer 24

atleast one has to be 1

Question 25

XOR

Answer 25

only one has to be 1

Question 26

character set

Answer 26

List of characters that can be understood by the computer. Each character has a unique binary code that is stored instead of the character.

Question 27

2 reasons why a programmer would use hexadecimal over binary

Answer 27

• hex is shorter than binary as a nibble can be represented by 1 hex character
• hex values are more reliable to enter

Question 28

2 benefits of normalised form with floating point

Answer 28

• Allows for more accuracy/precision from the given number of bits.
• The representation of each binary value is unique.