.xbm - X11 bitmap file format. Native file format of the X Window System used for storing cursor and icon bitmaps that are used in the X Window interface. XBM files are actually C language source files that are created to be read by a C compiler rather than a graphical display program. ( file extension )

.xdb - Norton AntiVirus Update File (Symantec).

.xdp - Xdataplot. These files contain only the name of the data file to which they refer. This allows viewing of large sequential datasets like those generated by electrophysiological recording.

.xfdf - Acrobat Forms Document (Adobe). ( file extension )

.xgo - Paradox Database related file .

.xif - Wang image file .

.xls - Excel Spreadsheet format. Native file format used by the Microsoft Excel spreadsheet program. ( file extension )

.xm - Extended Module format. Used by UNIX-type OSs for music. Also known as Fasttracker II format.

.xpm - X11 pixmap file format. Standard for storing monochome, gray-scale, and color pixmap data to disk under the X Window system. These files, like .xbm files, are C source code files, with each pixmap being defined as a static char array.

.xsql - Oracle XSQL Servlet XSQL Template File (Oracle Corporation).

.xwd - X Window Dump format. Used to store screen dumps created by the xwd client process in the X Window System. The image of any window or the background may be saved (dumped) to an .xwd file.

.xwp - Xerox Writer Text File ( file extension ).