Subject: IAUFGW official List of Registered Extensions in on the Web

From: bschlesinger at nssdca.gsfc.nasa.gov (Barry M. Schlesinger)
Date: 8 Sep 1995 16:40 EDT

The IAU FITS Working Group List of Registered Extensions is now 
available on the World Wide Web, at 
http://www.gsfc.nasa.gov/astro/fits/xtension.html.
It was previously available only in text form, at 
ftp://nssdc.gsfc.nasa.gov/pub/fits/xtension.lis

In order to allow reading software to identify whether or not it is 
capable of interpreting an extension, the extension type names, e. g., 
TABLE, BINTABLE, must be unique; that is, a given extension type name 
can identify only one structure.  To ensure this uniqueness, all 
extension type names and their meaning must be registered with the IAU 
FITS Working Group, even those extension types used at only one 
installation.  This Web page contains the current list, including 
links to those descriptive documents that are electronically
available.  It also provides information on how to register an
extension type name. 

				Barry Schlesinger
				FITS Support Office
				GSFC/ADF