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Bits and bytes – SMC Networks ADSL Barricade SMC7204BRA User Manual

Page 170

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Appendix B

174

Bits and bytes

Computers handle binary numbers by grouping them into units
of distinct sizes. The smallest unit is called a bit, and the most
commonly used unit is called a byte.

Definition (bit and byte):

A bit is a single binary digit, i.e., 0 or 1. A byte is a
group of eight consecutive bits (the number of bits
can vary with computers, but is almost always eight),
e.g., 11011001. The value of a byte ranges from 0
(00000000) to 255 (11111111).

The following shows the values of the eight digits in a byte along
with a sample value:

128's 64's 32's 16's 8's 4's 2's 1's

1

0

1

0

1

1

0

1

The decimal value of this byte is 173 (128 + 32 + 8 + 4 + 1 = 173).