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Bits, bytes and file sizes
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Photos, songs and games take up space. Units like bytes and megabytes tell us how much.
Small units
1 bit = a single 0 or 1.
1 nibble = 4 bits.
1 byte = 8 bits. One byte can store one character of text, such as the letter A.
1 nibble = 4 bits.
1 byte = 8 bits. One byte can store one character of text, such as the letter A.
Bigger units
Converting
Going to a smaller unit: multiply. 3 bytes = 3 × 8 = 24 bits.
Going to a bigger unit: divide. 4,000 KB = 4,000 ÷ 1,000 = 4 MB.
Going to a bigger unit: divide. 4,000 KB = 4,000 ÷ 1,000 = 4 MB.
A phone has 2 GB of free space. Each photo is 4 MB. How many photos fit? Use 1 GB = 1,000 MB.
- 2 GB = 2 × 1,000 = 2,000 MB.
- 2,000 ÷ 4 = 500
Answer: 500 photos
8 bits = 1 byte, 4 bits = 1 nibble. In decimal units each step up (KB, MB, GB, TB) is 1,000 times bigger; in binary units it is 1,024. Multiply to go smaller, divide to go bigger.
The interactive lesson includes the diagrams for this topic.
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