PDA

View Full Version : How does winzip work?



forrest44
15-07-2002, 06:08 PM
How does winzip compress files?

godfather
15-07-2002, 06:16 PM
Winzip uses compression.
Simply put (courtesy of the web)

Compression uses what is known as an algorithm (any set of instructions to be followed in order) to take a data file as input and make sure the output is a much smaller file. As an example, take a string of characters -

cheese and ham and more cheese

How else could this string of characters be represented? Well, we could make up a code. Notice the words "and" and "cheese" appear twice in the string, we could encode (compress) the string as follows:

b="cheese"
c="and"

to get:

b c ham c more b

If this is applied to a whole file only concentrating on frequently used code or text, the file could be made considerably smaller. This is an example of a fixed length code.