This comparison covers Character Set Comparison 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 7 of 11 in this topic. Use this comparison to connect the idea to the wider topic before moving on to questions and flashcards.
Character Set Comparison
| Set | Size | Bytes/Char | Coverage | Use Case |
|---|---|---|---|---|
| ASCII | 128 chars | 1 byte | English only | Legacy systems, simple text |
| Extended ASCII | 256 chars | 1 byte | Western Europe | Legacy, regional documents |
| Unicode (UTF-8) | 143,859 chars | 1-4 bytes | All languages | Web, modern apps, files |
| Unicode (UTF-16) | 143,859 chars | 2-4 bytes | All languages | Windows, Java internals |
| Unicode (UTF-32) | 143,859 chars | 4 bytes | All languages | Internal processing |
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.