Similar to スポットライト症候群

Codecademy

CodePlex

Collaborative real-time editor

Common Gateway Interface

.coop

.cr

Craigslist

.cu

Cuil

.cw

.cx

.cy

.cz

Data URI scheme

Datagram Congestion Control Protocol

Datagram Transport Layer Security

DAViCal

.de

Disqus

DNS zone transfer

.do

.dz

.ec