The Legacy (Zip 2.0)
compression option uses a traditional data compression algorithm, known as
deflate, that is supported by all versions of WinZip and virtually all other
Zip file utilities. The deflate method is generally considered to be a good
all-purpose compression algorithm for most types of files.
compression is the best choice when your mail recipient's
Zip utility is unknown or known to use older technology.
WinZip and WinZip Courier actually use the highest available
compression setting for the deflate method or maximum
deflate. This way you get the smallest, compatible Zip files