GRB is a raster image format associated with two calculator models produced by Hewlett Packard in the 1990s: the HP 48 and the HP 49. Both could be used for advanced algebraic operations and calculations and were considered innovative at the time of their release. GRB images most likely contain screen caps or other type of data connected to these devices. They are rare and difficult to open with regular image viewers.
JPEG JPG PNG GIF TIFF TIF BMP ICO EMF WMF AI PDF EPS PS EPI WEBP WEBPLL JP2 PCX TGA DWG DWF DXF DGN WMZ CGM DRW GBR PCT MIF PLT PCL SVG WPG CIN DCX DIS HRU MTV PRC RAD PIC RLA QRT SGI XBM XPM SWF CAL FITS PSD JXR BPG APNG DDS SVGZ CG4 FLIF