A file extension, or file name extension, is the letters immediately shown after the last period in a file name. For example, the file extension.txt has an extension of .txt. This extension allows the ...

(SYStem file) A file extension commonly used for DOS/Windows drivers, such as ANSI.SYS, HIMEM.SYS and KEYBOARD.SYS. See system file. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction ...

A file extension is a suffix that is added to the end of a file name after a dot. It is usually two to four letters long. File extensions help Windows and other operating systems to know the standard ...