Vector graphic format used by Xara Xtreme and its predecessors, Xara X and CorelXARA; can be used for editing photos, creating illustrations, and developing Web graphics; previously known as the Flare file format.
Program(s) that open xar files
Windows: Xara Xtreme (part of Xara Graphic Studio)
Unix: Xara Xtreme for Linux
Information from FileInfo.com - The File Extensions Resource.
http://www.fileinfo.com/extension/xar
