Binary: The Computer's Language
This key facts covers Binary: The Computer's Language within Binary & Hex for GCSE Computer Science. Revise Binary & Hex in 3.3 Data Representation for GCSE Computer Science with 16 exam-style questions and 22 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 5 of 15 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 5 of 15
Practice
16 questions
Recall
22 flashcards
Binary: The Computer's Language
Understanding Place Values in Binary:
Just like denary has place values (ones, tens, hundreds), binary has place values based on powers of 2:
Bit Position: 7 6 5 4 3 2 1 0
Place Value: 128 64 32 16 8 4 2 1
Example: 10110101
1×128 + 0×64 + 1×32 + 1×16 + 0×8 + 1×4 + 0×2 + 1×1
= 128 + 32 + 16 + 4 + 1 = 181 (denary)
Key Concepts:
- Bit: A single binary digit (0 or 1)
- 8-bit binary: Can represent 0-255 (28 = 256 values)
- 16-bit binary: Can represent 0-65,535 (216 = 65,536 values)
- Most Significant Bit (MSB): Leftmost bit (highest value)
- Least Significant Bit (LSB): Rightmost bit (lowest value)
Keep building this topic
Read this section alongside the surrounding pages in Binary & Hex. That gives you the full topic sequence instead of a single isolated revision point.
Practice Questions for Binary & Hex
Which of the following correctly describes the hexadecimal number system?
Explain why hexadecimal is used instead of binary when programmers write memory addresses and colour codes. Give three reasons.
Quick Recall Flashcards
16 questions on Binary & Hex — practise free
Instant marking, adaptive difficulty, and 22 spaced repetition flashcards. Free until your GCSEs.
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