What does .C stand for?

What does .C mean?

C	Comma Miscellaneous
C	Command Computing » Assembly
C	Commandant Business » Positions
C	Commandant Governmental » Military
C	Commission Governmental » Military
C	Commitment Business » Positions
C	Common meter Community » Music
C	Commons (designating bills introduced in the House of Commons) Governmental » Politics
C	Communication Computing » Networking
C	Communicator Business » Positions
C	Communism Governmental » US Government
C	Community Community
C	Compact Business » Products
C	Compact car Governmental » Transportation
C	Compare Computing » Software
C	Compassion Academic & Science » Psychology
C	Compensation Business » Positions
C	Competent Community » Law
C	Compiler Computing » Software
C	Complaining Community » Educational
C	Complete Business » General
C	Complete Governmental » NASA
C	Complex Academic & Science » Mathematics
C	Complexity Business » Products
C	Composition Community » Educational