Digital Repository at the University of Maryland (DRUM) 

DRUM Supported Formats

Currently supported formats

DRUM Format Support Policy

We want to provide support for as many file formats as possible. Over time, items stored in DRUM will be preserved as is, using a combination of time-honored techniques for data management and best practices for digital preservation. As for specific formats, however, the proprietary nature of many file types makes it impossible to guarantee much more than this. Put simply, our policy for file formats is:

  • everything put in will be retrievable
  • we will recognize as many files' formats as possible
  • we will support as many known file formats as possible

By "support", we mean "make useable in the future, using whatever combination of techniques (such as migration, emulation, etc.) is appropriate given the context of need". For supported formats, we might choose to bulk-transform files from a current format version to a future one, for instance. But we can't predict which services will be necessary down the road, so we'll continually monitor formats and techniques to ensure we can accomodate needs as they arise.

In the meantime, we can choose to "support" a format if we can gather enough documentation to capture how the format works. In particular, we collect file specifications, descriptions, and code samples. Unfortunately, this means that proprietary formats for which these materials are not publicly available cannot be supported in DRUM. We will still preserve these files, and in cases where those formats are native to tools supported by the Office of Information Technology, we will provide you with guidance on converting your files into formats we do support. It is also likely that for extremely popular but proprietary formats (such as Microsoft .doc, .xls, and .ppt), we will be able to help make files in those formats more useful in the future simply because their prevalence makes it likely tools will be available. Even so, we cannot guarantee this level of service without also having more information about the formats, so we will still list these formats as "known", not "supported".

Currently supported formats

In the table below, MIME type is the Multipurpose Internet Mail Extensions (MIME) type identifier; for more information on MIME, see the MIME RFCs or the MIME FAQ. Description is what most people use as the name for the format. Extensions are typical file name extensions (the part after the dot, e.g. the extension for "index.html" is "html"). These are not case-sensitive in DRUM, so either "sample.XML" or "sample.xml" will be recognized as XML. Level is DRUM's support level for each format:

  • supported: we fully support the format
  • known: we can recognize the format, but cannot guarantee full support
  • unsupported: we cannot recognize a format; these will be listed as "application/octet-stream", aka Unknown

Please see the full format policy below for a complete explanation of these terms.If your format is not listed below, see What to do if your format isn't listed at the bottom of this page.

MIME type Description Extensions Level
application/octet-stream Unknown
application/pdf Adobe PDF pdf known
text/xml XML xml known
text/plain Text txt, asc known
text/html HTML htm, html known
application/msword Microsoft Word doc known
application/ Microsoft Powerpoint ppt known
application/ Microsoft Excel xls known
application/marc MARC
image/jpeg JPEG jpeg, jpg known
image/gif GIF gif known
image/png image/png png known
image/tiff TIFF tiff, tif known
audio/x-aiff AIFF aiff, aif, aifc known
audio/basic audio/basic au, snd known
audio/x-wav WAV wav known
video/mpeg MPEG mpeg, mpg, mpe known
text/richtext RTF rtf known
application/vnd.visio Microsoft Visio vsd known
application/x-filemaker FMP3 fm known
image/x-ms-bmp BMP bmp known
application/x-photoshop Photoshop psd, pdd known
application/postscript Postscript ps, eps, ai known
video/quicktime Video Quicktime mov, qt known
audio/x-mpeg MPEG Audio mpa, abs, mpega known
application/ Microsoft Project mpp, mpx, mpd known
application/mathematica Mathematica ma known
application/x-latex LateX latex known
application/x-tex TeX tex known
application/x-dvi TeX dvi dvi known
application/sgml SGML sgm, sgml known
application/wordperfect5.1 WordPerfect wpd known
audio/x-pn-realaudio RealAudio ra, ram known
image/x-photo-cd Photo CD pcd known

What to do if your format isn't listed

We understand that there are always more formats to consider, and we would appreciate your help in identifying and studying the suitability of support for formats you care about. If we can't identify a format, DRUM will record it as "unknown", aka "application/octet-stream", but we would like to keep the percentage of supported format materials in DRUM as high as possible. Don't hesitate to contact us at if you have any questions or concerns.


DRUM is brought to you by the University of Maryland Libraries
University of Maryland, College Park, MD 20742-7011 (301)314-1328.
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