Storage units and file sizes

Storage units and file sizes

Bit to pebibyte in steps of 1024, and calculating image and sound file sizes.

Transcript

Data is measured in bits. A bit is a single zero or one. Four bits make a nibble, and eight bits make a byte.

Bigger units go up in steps of one thousand and twenty four: the kibibyte, mebibyte, gibibyte, tebibyte, and pebibyte.

To move to a bigger unit, divide by one thousand and twenty four. To move to a smaller unit, multiply. So two mebibytes is two thousand and forty eight kibibytes.

To find a file size, multiply the values to get the size in bits. Then divide by eight for bytes, and by one thousand and twenty four for each bigger unit.

A picture one thousand and twenty four by five hundred and twelve pixels, at sixteen bits, is about eight million bits. Divide by eight, then by one thousand and twenty four twice, and it is exactly one mebibyte.

A sound at eight thousand one hundred and ninety two hertz, sixteen bits, lasting eight seconds, is about a million bits. Divide by eight, then by one thousand and twenty four, and it is one hundred and twenty eight kibibytes.

Bits, bytes, then steps of one thousand and twenty four. Multiply to get bits, and divide to get the unit you need.

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Compression

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Unit 1 quiz

Ten questions with a think-time countdown and explained answers.

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