Yes its a Comic Reading Software... You can simply Change the extention to Rar from CBR and extract all Jpgs in a folder. Alternatively you can download CDisplayX (A comic reading software better then CDisplay
) from here :
*sourceforge.net/projects/cdisplayex
You can creating your own CBRs by Making a RAR archieve containing only JPGs and renaming extention to CBR...
(If you encounter a CBZ file.. Like RAR Its a ZIP file renamed to CBZ)