The legacy Microsoft Word format for text documents with formatting and layout
The DOC file format is the legacy binary format used by Microsoft Word for text documents. First introduced in the 1980s, it became the standard format for word processing documents through the 1990s and early 2000s, before being largely superseded by the DOCX format in 2007.
DOC files can contain formatted text, images, tables, charts, embedded objects, and various formatting elements. The format uses a proprietary binary structure, making it challenging to work with outside of Microsoft's applications, though compatibility has improved over the years.
Despite being officially replaced by DOCX in newer versions of Microsoft Office, the DOC format continues to be used in many organizations and remains supported for backward compatibility, particularly in environments where older software is still in use.
The DOC format uses Microsoft's Compound File Binary Format (a structured storage system similar to a file system within a file), allowing it to store multiple data streams and complex formatting information. The binary nature of the format made it efficient for the computing resources of its era but created challenges for interoperability with non-Microsoft applications.
DOC files are still essential in environments using older versions of Microsoft Office (pre-2007) or legacy systems that don't support newer formats. Government agencies, educational institutions, and some enterprises with delayed upgrade cycles often require DOC format for compatibility.
When sharing documents with users who might have older software or where maximum compatibility is essential, DOC format provides a tried-and-tested solution. It continues to serve as a common denominator format when the recipient's software capabilities are unknown.
Many organizations have extensive libraries of DOC templates developed over years or decades. These template systems often continue to use the DOC format due to the investment in their development and the cost of migration to newer formats.
Some legacy systems and applications that generate documents programmatically are designed specifically for the DOC format. These systems may continue to use DOC due to the complexity and cost of updating to support newer formats.
Historical documents from the 1990s and early 2000s are often archived in DOC format. While not ideal for long-term preservation (PDF/A is preferred), many organizations maintain archives of DOC files from earlier periods.
DOC files work with different Microsoft Office versions:
Many non-Microsoft applications support DOC files:
DOC files can be used across different operating systems:
| Feature | DOC | DOCX | RTF | ODT | |
|---|---|---|---|---|---|
| Openness | |||||
| Formatting Capabilities | |||||
| Backwards Compatibility | |||||
| File Size Efficiency | |||||
| Software Support | |||||
| Modern Features |
DOC excels in backward compatibility but falls behind newer formats in openness and modern features. DOCX provides better file size efficiency and modern capabilities, while PDF offers superior layout preservation. RTF serves as a more universal interchange format, and ODT provides an open-standard alternative to Microsoft's formats.
When converting from DOCX to DOC, be aware that newer features like advanced formatting, some graphics effects, and certain SmartArt elements may not convert perfectly. Use the "Save As" function in Word and select "Word 97-2003 Document (*.doc)" format. Review the document after conversion to catch any formatting issues.
Converting PDF to DOC can be challenging, especially for complex layouts. Use specialized PDF conversion software or Microsoft Word's built-in PDF import feature (available in newer versions). Expect to make manual adjustments after conversion, particularly for documents with complex tables, columns, or graphics.
RTF and ODT generally convert well to DOC format, though some advanced formatting may be simplified. Most word processors provide "Save As" or export options for DOC format. Check formatting of tables, headers/footers, and any specialized elements after conversion.
This is a common upgrade path and generally works well. Open the DOC file in a recent version of Word and save as DOCX. The conversion preserves most formatting while updating the file to the newer format. Microsoft Office includes a compatibility checker to identify potential issues during conversion.
Converting DOC to PDF produces a fixed-layout document that will look the same on all devices. Use the "Save As" or "Export to PDF" feature in your word processor. For best results, ensure all fonts are properly embedded and check the resolution settings for images if print quality is important.
DOC to HTML conversion often results in complex, nested tables and verbose code. Modern word processors offer improved HTML export options, but expect to clean up the code for web use. Consider using specialized conversion tools for better results if web publishing is the goal.