Sign & Magnitude

Represented by replacing the 128 in a bit pattern with a 0 or 1 to represent the sign. The rest of the numbers represent the magnitude as usual (value of number). The 0 represents positive (+) and 1 represents negative (-).

As shown in the diagram; the first binary string represents the number 255, the second number instead uses a sign and so represents -127.



The lowest number you can represent is -127 because the 128 column has to be replaced by the negative sign. You can still represent numbers up to 255.

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