Computer Science

a word used in front of a number to represent a multiple of that number

putting a sequence of characters into an agreed format

a measure of how much binary data a file contains

Text file size calculation

Representation using binary sequences

Representing text using ASCII and Unicode

Representing bitmap images

Bitmap file size calculation

Representation of sound

Calculation of sound file sizes

Metadata

In this unit, pupils will discover how letters, images and sounds are represented with binary digits. They will also explore the factors that impact the quality of those representations and investigate the effects these quality choices have on file size.

Representation of text, images and sound

Put these quantities of bytes into order, smallest to largest:

How many bits does ASCII use per character?

Unicode uses more bits to represent characters

If a text file contains 100 characters, what is the file size in bits using ASCII encoding?

A text document has 50 characters. Calculate the file size in bytes when using 32-bit Unicode encoding.

What is a digit of a binary number that can only be 1 or 0 called?

matches characters to unique binary sequences

data that has been processed to provide meaning

a digit of a binary number that can only be 1 or 0

How many different characters can 8-bit ASCII represent?

What is the main advantage of Unicode over ASCII?

Text file size calculation

Lesson outcome