See also: Glossary

.ART
files are used by AOL in thier online service and are being supported for display in thier AOLPRESS browser/editor from GNN. The .ART file format and development tools were created by Johnson-Grace Corporation and appear to be available to developers only (or possibly not available since thier aquisition by AOL)
.BAT
Batch Files - DOS COMMAND.COM
.COM
Command - DOS Loader
.DBF and .NDX/.MDX/.NTX/.IDX
xBase database files and related index types for dBase, Clipper, and Foxpro
.EXE
Executable - DOS Loader
.GIF
files are the defacto standard for raster image graphics on the World Wide Web. see also: services
.HEX
Hex Files
.HLP
WinHelp or Windows help files
.HTM/.HTML
Hyper Text Markup Language. A subset of SGML
ISBN
A system for numbering books
PCL
Printer Control Language.
PDF
Portable Document Format. From Adobe Systems Corp
PGML
The Precision Graphics Markup Language is the Adobe / IBM / Netscape / SUN proposed extension of HTML for Vector Graphics. Although it was submited before the VML proposal, the W3 Commity commented on VML (very positivly) and has not (as of 98/07/28) commented on PGML. (Read: W3 is owned by Microsoft)
.TXT
text files. On PC systems, these are ASCII text
.VCF
v-card .VCF files; they are an electronic version of a business card (rfc 2426) supported by yahoo, palm pilots, etc.... (see: http://www.imc.org/pdi/ or http://info.internet.isi.edu/in-notes/rfc/files/rfc2426.txt) that Outlook automatically attaches to every email.
.VML
The Vector Markup Language is the Microsoft / Hewlett Packard / Visio / Autodesk / MacroMedia proposed extension of HTML for Vector Graphics. VML is defined as a part of XML
.WMF
Windows Meta File. see also: Caolán McNamara's Guide for non-windows programmers

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