A kilobyte is not 1000 bytes but 1024, because machines count in powers of two rather than on ten human fingers. Eight bits side by side cover 256 values: the rightmost bit flips every tick, while each bit further left flips exactly half as often. The very same byte 11111111 reads as 255 when unsigned, yet under two’s complement the top bit carries a weight of −128 and that byte means −1. The letter A is not stored as the shape of an A either; the machine keeps only the code 65 and lets a font draw the shape.
A kilobyte is not 1000 bytes but 1024, because machines count in powers of two rather than on ten human fingers. Eight bits side by side cover 256 values: the rightmost bit flips every tick, while each bit further left flips exactly half as often. The very same byte 11111111 reads as 255 when unsigned, yet under two’s complement the top bit carries a weight of −128 and that byte means −1. The letter A is not stored as the shape of an A either; the machine keeps only the code 65 and lets a font draw the shape.
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