Binary, hex and data representation
Mostly method: place values, conversions and a few rules for units.
Conversions
Binary place values double from the right: 1, 2, 4, 8 and so on. Each hexadecimal digit stands for four binary digits, which makes binary to hex the quickest conversion.
| 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 |
Units, images and sound
A bit is a 0 or a 1, and 8 bits make a byte. An image file grows with its width, height and colour depth; a sound file with its sample rate, bit depth and length.
| Unit | Size |
|---|---|
| Bit | 0 or 1 |
| Nibble | 4 bits |
| Byte | 8 bits |
| Kilobyte | 1,000 bytes |
Logic
| A | B | A AND B | A OR B |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 0 | 1 | 0 | 1 |
| 1 | 0 | 0 | 1 |
| 1 | 1 | 1 | 1 |
Printable binary and hex practiceIn the Shop Questions
Why do computers use binary?
Their circuits have two states, on and off, which map neatly onto 1 and 0.
Related
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