I think that highenergy did not give a proper description op DJVU because it is already installed in Pardus by default, and he just asks to update the package.
What are DjVu files ?
DjVu is excellent compression format for storing and viewing documents of one or more pages, in colour or black and white. It far outperforms other bitmap formats (e.g. GIF, PNG) in respect to file size when applied to scanned documents, and is also very efficient for documents which have originated in digital form (e.g. PDFs). DjVu behaves just like an image file format and is therefore not dependent on any particular fonts or other resources being available. Think of DjVu as an electronic photocopy in a surprisingly small file size, and you've got the idea. DjVu is currently developed by LizardTech who provide commercial compressors and free browser plugins. DjVuLibre is open-source GPL version of their library which can be found on Sourceforge.
Features
* Works for colour and bitonal (black and white) documents.
* Supports multipage documents.
* Does not rely on installed fonts (unlike PDF).
* The image can be rotated by 90 degrees for better viewing.
* Invoke via the command line for power-users.