cs2010 Notes: 09-02 Data

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The basic unit of data, what computers really store, is the bit: A single off/on, 0/1, false/true value.
We want to be able to store complex stuff, like a movie. How?
Those things are pretty far apart. Let’s build in both directions and meet in the middle.

One bit allows for two distinct values.
We could represent whatever with those values: 0 and 1, A and B, 37 and 381.
But a useful thing to represent is non-negative integers from 0: If we have two, it’s 0 and 1.
If we have two bits, that’s four distinct values, integers from 0: 0, 1, 2, 3
- Show the values in binary
Three bits?
- Show the values in binary
Eight bits?
N bits?
Modern computers don’t usually deal with single bits. Instead they deal with bytes (or groups of 8 bits) and common integer sizes: 16, 32, and 64 bit groups.

(Most) human eyes sees: Red, Green, Blue
If we use 8 bits each for “how red”, “how green”, and “how blue”, we can represent 16 million different colors.
Put 1920x1080 colored pixels together and you have a 1080p display. 3840x2160 and you’ve got a 4k display

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Nat Tuck