文档介绍：How Bits and Bytes Work
by Marshall Brain
If you have used puter for more than five
minutes, then you have heard the words bits and
bytes. Both RAM and hard disk capacities are
measured in bytes, as are file sizes when you
examine them in a file viewer.
You might hear an advertisement that says, "This
computer has a 32-bit Pentium processor with 64
megabytes of RAM and gigabytes of hard
disk space." And many HowStuffWorks articles
talk about bytes (for example, How CDs Work). In
this article, we will discuss bits and bytes so that
you have plete understanding.
Decimal Numbers
The easiest way to understand bits is pare them to something you know: digits. A digit is a
single place that can hold numerical values between 0 and 9. Digits are bined
together in groups to create larger numbers. For example, 6,357 has four digits. It is understood
that in the number 6,357, the 7 is filling the "1s place," while the 5 is filling the 10s place, the 3 is
filling the 100s place and the 6 is filling the 1,000s place. So you could express things this way if
you wanted to be explicit:
(6 * 1000) + (3 * 100) + (5 * 10) + (7 * 1) = 6000 + 300 + 50 + 7 = 6357
Another way to express it would be to use powers of 10. Assuming that we are going to
represent the concept of "raised to the power of" with the "^" symbol (so "10 squared" is written
as "10