DE FACTO STANDARD
A format, language, or protocol that has become a standardnot because it has been approved by a standards organization but because it is widely used and recognized by the industry as being standard. Some examples of de facto standards include:
Hayes command set for controlling modems
Kermit Communications Protocol
XmodemCommunications Protocol
Hewlett-Packard Printer Control Language (PCL) for laser printers
PostScript page description languagefor laser printers
The QWERTY system for typewriters and keyboards
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