IETF SGML document
File type: Document file
An sgml file extension is related to the Standard Generalized Markup Language file format used to transport of documents in a format independent of the device, system or application.
Found 2 different file type records with the same sgml filename suffix.
File type category:
Document file
Date updated: November 7, 2017
The SGML file extension is associated with SGML - Standard Generalized Markup Language and used for files written in this language.
SGML is an international standard for the transport of documents in a format independent of the device, system or application and is constantly developed and revised.
HTML is an application of SGML, while XML is a metalanguage based on SGML, used for creating XML applications.
MIME types:
text/sgml
text/x-sgml
application/sgml
application/x-sgml
Use compatible tools to work with *.sgml files.
Conversion to other formats is not possible.
File type category:
Document file
Date updated: October 2, 2026
Encoded Archival Description is a standard for encoding archival finding aids, maintained by the Library of Congress in partnership with the Society of American Archivists.
The original EAD standard used SGML, while later EAD versions also support XML-based encoding. An EAD document can contain descriptive, administrative and structural information such as collection scope, arrangement, access conditions and descriptions of components within a collection.
The EAD definition conforms to SGML/XML specifications associated with ISO 8879 and has been tested with a wide variety of existing SGML/XML software. Its DTD includes switches for turning off features used only in SGML applications and enabling features used in XML applications.
An EAD SGML document can be opened as text in a text editor or in an SGML-aware editor. To validate or process it correctly, the editor or archival system may also need the EAD DTD and any referenced SGML declaration.
Because SGML and XML are not identical, a standard XML editor may display the file as text without validating it. Archival collection-management and finding-aid systems that support EAD can provide more useful viewing and processing.
An EAD SGML document can be converted to an XML-based EAD document with an SGML/XML processing tool and the appropriate EAD DTD or transformation. The result should be validated against the target EAD definition.
Conversion to another archival format is normally performed by an archival system or a custom transformation, because the document's collection hierarchy and descriptive elements need to be mapped to the target format.
Language
