SMC Networks SMC7204BRA manual Appendix B, Binary Numbers, Definition binary numbers

APPENDIX B

Binary Numbers

In everyday life, we use the decimal system of numbers. In decimal, numbers are written using the ten digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Computers, however, do not use decimal. Instead, they use binary.

Definition (binary numbers):

Binary numbers are numbers written using only the two digits 0 and 1, e.g. 110100.

Hint: Does "base ten" sound familiar? (Think grade school). Base ten is just another name for decimal. Similarly, base two is binary.

Just as each digit in a decimal number represents a multiple of 10 (1, 10, 100, 1000, 10,000, etc.), each digit in a binary number represents a multiple of 2 (1, 2, 4, 8, 16, etc.). For example:

	Decimal		Binary
1,000's 100's 10's 1's			8's	4's	2's	1's
-	-	1 3	= 1	1	0	1

Also, since binary uses only two digits to represent all numbers, a binary number has more digits than the same number in decimal. In the example above, you can see that the decimal number 13 is the same as the binary number 1101 (8 + 4 + 1 = 13).

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