3.5.3.1 Units of Information: Bits and Bytes.

Question 1

Define a bit.

Answer 1

A fundamental unit of information that can only take two values, 1 and 0.

Question 2

How are bits represented in computers?

Answer 2

Using high or low currents.

Question 3

Define a collection of bits.

Answer 3

A Byte.

Question 4

How are bits and bytes notated?

Answer 4

A bit is notated with a lowercase ‘b’ and a Byte with an uppercase ‘B’.

Question 5

Outline representing values with bits.

Answer 5

The number of different values that can be represented with a specified number of bits varies with the number of bits. The more bits that are assigned to a number, the greater the number of values that can be represented.

More specifically there are 2n different values, represented with n bits
e.g. using just 2 bits, there are four possible permutations of the bit and hence four different values that can be represented (2^2 = 2 x 2 = 4).

Question 6

If we use a Byte, how many different values can be represented?

Answer 6

(2^8) = (2 x 2 x 2 x 2 x 2 x 2 x 2 x 2) = 256 possible representations.