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The Lego Building Blocks
The Lego Building Blocks
Imagine you're building with Lego. A single brick (bit) is tiny. Eight bricks make a small block (byte - enough for one letter). 1,024 small blocks make a bag (kilobyte - a short email). 1,024 bags make a box (megabyte - a photo). 1,024 boxes make a crate (gigabyte - a movie). 1,024 crates make a shipping container (terabyte - your entire photo library). Each level is roughly 1,000× bigger than the last!
Deep Dive: Why 1024 Instead of 1000?
Computers work in binary (base 2), so everything is powers of 2. The closest power of 2 to 1,000 is 210 = 1,024. This creates an interesting situation:
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Exam Tips - Storage Units
Most common exam questions:
- "How many bytes in a kilobyte?" → 1,024 bytes (NOT 1,000!)
- "Convert X KB to MB" → Divide by 1,024
- "Convert X GB to MB" → Multiply by 1,024
- "How many MB in 2 GB?" → 2 × 1,024 = 2,048 MB
- File size calculations → Total size ÷ file size = number of files
Key conversion facts to memorize:
- 1 byte = 8 bits (ALWAYS 8, never changes)
- 1 KB = 1,024 bytes
- 1 MB = 1,024 KB
- 1 GB = 1,024 MB
- 1 TB = 1,024 GB
Common mistakes to avoid:
- Using 1,000 instead of 1,024 - WRONG for binary calculations!
- Confusing bits (b) with bytes (B) - lowercase vs uppercase matters!
- Multiplying when you should divide (or vice versa)
- Forgetting to convert to the same units before calculations
- Not showing working - always show your calculation steps!
Calculation strategy:
- Read carefully: bits or bytes? KB, MB, or GB?
- Convert to same units: Both in MB or both in GB
- Choose operation: Smaller→Larger = divide, Larger→Smaller = multiply
- Show working: Write each step clearly
- Check answer: Does it make sense? (GB should be smaller number than MB)
Now try it yourself
Quiz · Question 1 of 15
How many bits make up one nibble?
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This topic in real past papers
Every real exam question we've found on storage units, with a full worked answer.