cdma2000
This standard is evolution of cdmaOne.It can use of a wider spectrum than CDMA and therefore can transmit and receive information faster and more efficiently, making fast Internet data, video, and CD-quality music transmission possible.The cdma2000 1X technology is seen as interim before KDDI eventually migrates to third generation (3G) services.There are new cdma2000 variants called cdma2000 1X, 1X-EV-DV, 1X EV-DO, and cdma2000 3X. They deliver 3G services while occupying a very small amount of current spectrum (1.25 MHz per carrier) as opposed to UMTS which requires completely new spectrum.
That is why cddma2000 is considered slightly more technologically advanced than the competing W-CDMA standard. CDMA2000 is not constrained to only the IMT band; it is defined to operate in existing cellular and PCS spectrum as well as IMT spectrum, thereby maximizing flexibility for operators. Cdma2000 is expected to be compatible with CDMA and GSM/TDMA networks so that GSM networks can "overlay" a cdma2000 network over their GSM networks.Peak data rate of 2.4 Mbps on the forward link and 307 kbps on the reverse link provides unprecedented speed. Average throughput on a loaded sector is an estimated 600 kbps on the forward link and 220 kbps on the reverse link.

cdmaOne
Digital cellular standard based on American Interim Standard-95 (IS-95). It is often called a 2.5G standard for its high voice quality, high-speed data transmission, and smooth hand-over. Because cdmaOne is recognized in many countries, this makes international roaming service easier. cdmaOne was first introduced in Japan in July 1998. IS-95 has 14.4bit/sec bandwidth and allows fax sevices. Later versions of IS-95 incorporated improved data transmission speed. IS-95B can transmit packet at 64bit/sec speed, when IS-95C already allows 144-153kbit/sec.

cdmaOne
3G wireless standard

Chaku-moji
A 10-character message (5 yen per message excluding tax), which can be sent along with a phone call. The message is displayed on the receiver's cellphone screen as the phone rings.

chara den
(character denwa) - a feature available on the DoCoMo’s FOMA 900i series handsets with the capability of displaying moving characters (avatar-based) on the phone’s screen instead of caller’s face during a videophone call. By pressing assigned keys the user can make the animated character to move or change expressions during a videoconference. The replacement of live video with animated characters is good for the network transmission ability and, probably, cell phone’s battery.

cHTML (compact HTML)
cHTML is a compact variety of HTML that is to i-Mode as WML is to WAP.

Cmode
Cmode is a service that lets users of the i-mode wireless Internet service, provided by NTT DoCoMo, buy soft drinks and mobile content such as ringtones, wallpapers and apps from vending machines using their cellular handsets. The Cmode (or gshimoh in Japanese interpretation) vending machines are equipped with a special barcode reader that identifies whether the user is a Club Cmode member, by scanning a barcode displayed on user's cellphone screen. The second generation of Cmode machines called shimo2 can conduct transactions based on contactless payment system FeliCa built in DoCoMofs wallet-phones.