Bits, Nybbles, and Bytes

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• Bits, Nybbles, and Bytes

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Information

• What it takes to answer a question
• Bit -- yes or no --gt simplest answer
• 1 or 0, high or low
• Answers can be measured in exact number of bits
• Numeric Facts
• place-value numbers needed to represent it

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Information

• Non-numeric
• place-value numbers used as codes
• character sets
• index values
• Why Binary and not another base?

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Bits

• Nybble (4)
• Byte (8)
• Word (16)
• Dword (32)
• Qword (64)

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Numbers

• 16 bits
• -32,768 to 32,767
• 32 bits
• -2,147,483,648 to 2,147,483,647
• 64 bits
• 0 to 1.8 x 1019
• 9,223,372,036,854,775,807

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ASCII

• 7 bits pure symbol (128 different characters)
• Control Characters 0-31, 127
• Extended ASCII -- 128-255
• high-bit-set characters

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Unicode

• 16 -bit numbers
• UCS-2 63,488 symbols
• UCS-2 (2 16-bit words) million plus symbols