.Z01 - .Z05 - WinZip Split Compressed Archive (WinZip International LLC (a Corel Company)).
.Z - UNIX compression utility that is used to compress single files.
.ZDB - Quicken On-line File (Intuit Inc.) ( file extension ).
.ZIP - Zip file format. A PC compression utility that can compress multiple files into one archive.
.ZIP2 - StuffIt Deluxe 8.5 Archive (Aladdin Systems, Inc.) ( file extension ).
.ZIPX - StuffIt Deluxe 8.5 Archive (Aladdin Systems, Inc.) ( file extension ).
.ZIX - Quicken online file ( file extension zix ).
.ZKA - Quicken 6 File (Intuit Inc.).
.ZQ0 to .ZQ9 - ZoneAlarm Mailsafe (Zone Labs) (file extension).
.ZSH - Unix zsh Shell Script (file extension).