File extension
.doc
Palm Pilot DOC files
.doc files are usually Microsoft Word binary documents: a legacy word-processing format stored in the OLE Compound File (Structured Storage) container holding formatted text, images, and embedded objects.
Known meanings
Formats and reference material for .doc
Palm Pilot DOC files
Palm Pilot DOC files
Microsoft Word 6.0 Binary File Format (MS Word)
Microsoft Word 6.0 Binary File Format (MS Word)
Microsoft Word 6.0 Binary File Format (as TXT file)
Microsoft Word 6.0 Binary File Format (as TXT file)
Microsoft Word 8/Word 97 Format - more complete version (HTML FILE)
Microsoft Word 8/Word 97 Format - more complete version (HTML FILE)
Tools to analyse the file formats of Microsoft's OLE applications and to extract the text portion out of Word 6/7/8 files (perl)
Tools to analyse the file formats of Microsoft's OLE applications and to extract the text portion out of Word 6/7/8 files (perl)
Palm Pilot DOC file format
Palm Pilot DOC file format
Microsoft Word 97 Format (including bidirectional support)
Microsoft Word 97 Format (including bidirectional support)
Microsoft Word 2 Format (RTF)
Microsoft Word 2 Format (RTF)
Microsoft Word 5.0 (PC) Binary File Format
Microsoft Word 5.0 (PC) Binary File Format
Microsoft Word 8/Word 97 Format (HTML file)
Microsoft Word 8/Word 97 Format (HTML file)
Details
Format notes
Microsoft Word Document (.doc)
For most of its history the .doc extension has meant a Microsoft Word document
in Word’s binary format, the default for Word up to and including Word 2003.
Rather than a flat file, a classic .doc is stored inside an OLE Compound File
(also called Structured Storage) — a small file system within a file, containing
named streams such as WordDocument, 1Table/0Table, and Data. The
WordDocument stream begins with the File Information Block (FIB), which points
to the text and the formatting structures scattered through the streams.
A binary Word document can hold formatted text, styles, tables, images, fields,
revision tracking, embedded OLE objects, and VBA macro projects. In 2007 Word
switched its default to the XML-based, ZIP-packaged .docx (Office Open XML), so
.doc is now the legacy binary format while .docx is the modern one; the two
are structurally unrelated despite the similar names.
Other Uses Of .doc
The extension is overloaded. It has also been used for Palm Pilot “DOC” e-book
files and, generically, for plain-text documents, so a .doc should be
identified by its content (for example the OLE compound-file signature
D0 CF 11 E0 A1 B1 1A E1) rather than by extension alone.
Preservation And Security Notes
Because binary Word documents can embed VBA macros and OLE objects, an untrusted
.doc should be treated as potential active content: open with macros disabled
and object activation blocked. For preservation, migrating to an open, documented
format (Office Open XML, ODF, or PDF/A) while retaining the original is advisable,
since faithful rendering depends on Word’s layout behavior and available fonts.
Further Reading
- [MS-DOC] Word (.doc) Binary File Format:
https://learn.microsoft.com/openspecs/office_file_formats/ms-doc/ - Compound File Binary Format [MS-CFB]:
https://learn.microsoft.com/openspecs/windows_protocols/ms-cfb/