1. CDMA technology operating in the Cellular radio frequency band.
2. CDMA technology operating in the ESMR radio frequency band.
The Cellular and ESMR bands are different and do not overlap, but are both commonly referred to as the "800" band, since they are both ranges near 800 MHz.
The Cellular band is closer to 850 MHz, though, so Phone Scoop currently distinguishes between the two by designating the Cellular band "850" and the ESMR band "800". Therefore if you see "CDMA 800" on this web site, it means CDMA technology in the ESMR band used by Sprint Nextel.
The ESMR band was originally used for iDEN service.