📦 Topic 1

Data Representation

Discover how computers represent numbers, text, images and sound using binary data—and how storage and compression make that data practical.

One idea at a time. Begin with binary and hexadecimal, then see how the same bits represent text, images and sound.

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Follow the sequence or jump directly to the concept you need.

1.1

Binary and Hexadecimal

Understand how computers use binary and why hexadecimal provides a shorter way to represent binary values.

FoundationOpen lesson
1.2

Binary Manipulation and Negative Numbers

Explore binary addition, logical shifts and how signed binary values represent negative numbers.

Core skillOpen lesson
1.3A

Text Representation

Learn how character sets such as ASCII and Unicode give each character a binary code.

Text dataOpen lesson
1.3B

Image Representation

See how pixels, resolution and colour depth determine the quality and file size of a bitmap image.

Image dataOpen lesson
1.3C

Sound Representation

Discover how sampling rate, sample resolution and duration affect digital sound quality and file size.

Sound dataOpen lesson
1.4

Measuring Data Storage

Understand bits, bytes, kibibytes, mebibytes and the units used to measure stored data.

Storage unitsOpen lesson
1.5

Data Compression

Compare lossy and lossless compression and understand why reducing file size can be useful.

Final lessonOpen lesson
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