Scenario: Your friend sends you a message: "Café resumé"
- Friend's system: Saves in UTF-8 (é = 2 bytes: 0xC3 0xA9)
- Your system: Reads as ASCII (each byte = one character)
- Result: "Café resumé" (scrambled - this is called mojibake)
Why? Mismatch between encoding (UTF-8) and decoding (ASCII). The bytes 0xC3 0xA9 mean 'é' in UTF-8, but 'é' in ASCII.
Solution: Both systems must use the same character set (UTF-8 is now the web standard).
This deep dive covers Real-World Example: The Mojibake Problem within Character Sets for GCSE Computer Science. Revise Character Sets in 3.3 Data Representation for GCSE Computer Science with 15 exam-style questions and 18 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 8 of 11 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Character Sets
How many bits does standard ASCII use to represent each character?
Explain why using Unicode to store a text file produces a larger file than using ASCII to store the same text.