C	Site configuration for Secure Remote (CheckPoint VPN)
C	C code
C--	Sphinx C-- Source code
C00	Ventura Publisher Print file
C01	Typhoon wave
C86	Computer Innovation (C86) Source code
CA	Telnet Server Initial cache data file
CAB	Microsoft cabinet file (program files compressed for software distribution)
CAC	dBase IV Executable file
CACHE	Shared Cache file
CAD	Softdesk Drafix Cad file
CAG	Catalog file (Microsoft Clip Gallery v. 2.x,3.x,4.x)
CAL	SuperCalc 4/5 Spreadsheet
CAL	Calendar schedule data file
CAL	CALS Compressed Bitmap
CAM	Casio camera file
CAN	Navigator Fax
CAP	Compressed music file
CAP	Telix Session Capture file
CAP	Ventura Publisher Caption
CAR	AtHome assistant file
CAS	Comma-delimited ASCII file
CAT	dBase Catalogue file
CAT	Quicken IntelliCharge categorization file
CB	Microsoft clean boot file
CBC	CubiCalc Fuzzy Logic System file
CBF	Vietcong (game) Pterodon big file
CBI	Column binary file (used in IBM mainframe systems)
CBL	Cobol Source code
CBM	XLib Compiled Bitmap
CBR	Comic book or paperback RAR file (decompress with RAR utility)
CBT	Generic Computer based training file
CBZ	Comic book or paperback ZIP file (decompress with WinZip or similar program)
CC	C++ Source code
CC	Visual dBASE custom class file
CC3	Close Combat 3 file
CCA	cc:mail archive file
CCB	Visual Basic Animated Button configuration file
CCC	Curtain Call Native bitmap graphic
CCD	Elaborate Bytes Clone CD mapfile for creating and reading .img files
CCE	Data file (Calendar Creator Plus)
CCF	Symphony Communications Configuration file
CCF	Multimedia Viewer configuration file used in OS/2
CCH	Corel Chart
CCL	Intalk Communication Command Language
CCM	Lotus CC:Mail "box" file (for example, INBOX.CCM)
CCO	XBTX Graphics
CCO	CyberChat data file
CCT	Macromedia Director Shockwave cast file
CDA	CD Audio Track
CDB	CardScan Database (CardScan)
CDB	TCU Turbo C Utilities Main database
CDB	Conceptual model backup file (PowerDesigner)
CDB	Clipboard file
CDF	Microsoft Channel Definition Format
CDF	Netcdf Graphic file
CDFS	Compact Disk filing system (WindRiver)
CDI	Phillips Compact Disk Interactive file
CDK	Atari Calamus Document
CDM	Visual dBASE custom data module
CDM	Conceptual data model file (PowerDesigner Data Architect) (Sybase)
CDM	Conceptual model file (PowerDesigner)
CDR	Raw Audio-CD data file
CDR	Corel Vector Graphic Drawing File
CDR	Corel Draw Vector drawing file
CDT	CorelDraw Data file
CDT	Corel Draw template
CDX	Microsoft's Visual Foxpro index
CDX	Corel Draw compressed drawing
CE	The FarSide Computer Calendar Main CE file
CEF	Cruzer encrypted file (used to secure files on Cruzer USB flash drives)
CEG	Tempra Show Bitmap graphic
CEL	AutoDesk Animator Cel Image
CEL	CIMFast Event Language file
CER	Certificate file (MIME x-x509-ca-cert)
CEX	Caddie Exchange file
CF	Imake Configurtion file
CFB	Comptons Multimedia file
CFG	Configuration file
CFL	CorelFLOW Chart
CFM	Visual dBASE Windows customer form
CFM	Corel FontMaster file
CFM	Creative FM-Music
CFM	ColdFusion template
CFN	Atari Calamus Font data file
CFO	TCU Turbo C Utilities C form object
CFP	The Complete Fax Portable fax file
CGA	Ventura Publisher Display font file
CGI	Common gateway interface script
CGM	Computer Graphic Metafile
CH	Clipper 5 Header
CH	OS/2 configuration file
CH3	Harvard Graphics 3.0 Chart
CH4	Charisma 4.0 Presentation
CHD	FontChameleon Font descriptor
CHF	pcAnywhere remote control file
CHI	ChiWriter Document
CHK	WordPerfect for Windows Temporary file
CHK	File fragments saved by Windows Disk Defragmenter or ScanDisk
CHL	Configuration History Log
CHM	Compiled HTML file
CHN	Ethnograph Data file
CHP	Ventura Publisher Chapter file
CHR	Character Sets (Font file)
CHT	Harvard Graphics Vector file
CHT	ChartMaster dBase Interface file
CHT	ChartViewer file
CIF	Easy CD Creator image
CIF	pcAnywhere caller file
CIF	CalTech Intermediate Graphic
CIL	Clip Gallery download package file
CIM	Sim City 2000 file
CIN	OS/2 change control file that tracks changes to an INI file
CIX	TCU Turbo C Utilities Database Index
CK1	iD/Apogee Commander Keen 1 data
CK2	iD/Apogee Commander Keen 2 data
CK3	iD/Apogee Commander Keen 3 data
CK4	iD/Apogee Commander Keen 4 data
CK5	iD/Apogee Commander Keen 5 data
CK6	iD/Apogee Commander Keen 6 data
CKB	Borland C++ Keyboard mapping file
CKF	Casio Keyboard File
CL	Generic LISP Source code
CL3	Layout file (Adaptec Easy CD Creator)
CLASS	Java class
CLC	TI-83 Plus Flash Debugger file
CLG	Disk Catalog database
CLL	Cricket Software Clicker File
CLO	Cloe Image
CLP	Quattro Pro Clip art
CLP	Clipper 5 Compiler Script
CLP	Windows Clipboard
CLR	PhotStyler Color defintion
CLR	1st Reader Binary color screen image
CLS	C++ Class Definition
CLS	Visual Basic Class Module
CLX	Macro ToolsWorks Macro file
CLX	Rational XDE file
CLX	Adobe file
CM	Craftman Data
CMA	Database file in plain text format (APPLIX TM1)
CMD	DOS CP/M command file
CMD	dBase-II program file
CMD	1st Reader External Command Menu
CMD	Command file for Windows NT (similar to a DOS .BAT file), OS/2
CMF	Corel Metafile
CMG	Chessmaster saved game
CMK	Card Shop Plus file
CMM	CEnvi Batch file
CMP	Address document
CMP	CorelDRAW 4.0 Postscript Printer Header
CMP	Route 66 Address Document
CMP	Microsoft Word for DOS User dictionary
CMP	JPEG Bitmap
CMR	MediaPlayer Movie
CMV	Corel Move animation
CMX	Corel Presentation Exchange image
CMYK	Raw cyan, magenta, yellow, and black bytes file
CNC	CNC General Program data
CNF	Configuration file used by Telnet, Windows, and other applications with varying internal formats
CNM	Windows application menu options and setup file
CNQ	Compuworks Design Shop file
CNT	Windows (or other) system content files for the help index and other purposes
CNV	WordPerfect for Windows Temporary file
CNV	Conversion files (WS_FTP Pro) files that will be converted from (Example) "HTML-"HTM" for upload
CNV	Word for Windows Data conversion support file
COB	COBOL Source code
COB	trueSpace 2 object
COD	FORTRAN Compiled code
COD	dBase Application Generator Template source file
COD	Video Text file
COD	Microsoft C compiler output as displayable machine language/assembler with original C as comments
COE	Xilinx coefficient
COL	Microsoft Multiplan Spreadsheet
COL	AutoDesk Animator Color Palette
COM	Command file (program)
CON	Simdir Configuration file
CP	CryptoPad.NET Encrypted document
CP8	CP8 256 Gray Scale image
CPD	Fax Cover document
CPD	Complaints Desk Script
CPD	Corel PrintOffice file (drawing)
CPE	Fax Cover document
CPF	The Complete Fax (Fax file)
CPF	CORDIS CPF Editor Contract Preparation Form Submission File
CPF	Color palette file
CPH	Image file (Corel Print House) see CPO
CPI	ColorLab Processed Image bitmap
CPI	Microsoft MS-DOS code page information
CPJ	CeQuadrant CD Project
CPL	Compel Presentation
CPL	Corel color palette
CPL	Control Panel Module
CPM	Turbo Pascal DOS file
CPMZ	Used to exchange project data between Miradi and ConPro
CPO	Image file (Corel Print Office)
CPP	CA-Cricket Presents presentation
CPP	C++ Source code
CPR	Corel Presents presentation
CPS	Coloured postscript
CPS	Central Point PC Tools Backup
CPT	Macintosh Compressed Archive
CPT	dBase Encrypted Memo
CPT	CA-Cricket Presents Template
CPT	Corel Photo-Paint image
CPX	Corel Presentation Exchange compressed drawing
CPY	Data file (Copy Books)
CPZ	COMPOZ Music Text
CRC	Check file (Win-SFV32)(Fantasia Software)
CRC	Circular reference file (Pro/Engineer)
CRD	Microsoft Windows 3.x Cardfile
CRF	Zortech C++ cross-reference
CRH	Image file (Microsoft Golf)
CRP	Visual dBASE custom report
CRP	dBase IV Encrypted database
CRP	Corel Presents run-time presentation
CRS	WordPerfect 5.1 for Windows File Conversion resource
CRT	Oracle Terminal settings information
CRT	Crontab file)
CRT	Certificate file
CRU	CRUSH Compressed archive
CS1	Sinar CaptureShop raw file for Macintosh
CS16	Sinar CaptureShop raw file for Macintosh
CS4	Sinar CaptureShop raw file for Macintosh
CSA	Comma deliminated text
CSC	Corel script
CSG	Statistica/w Graph file
CSH	C shell script files (Hamilton Labs)
CSM	Script file (Kodak Dc265 Camera)
CSM	Borland C++ 4.5 Precompiled header
CSO	Customer service data and outcome file
CSP	PC Emcee On-Screen image
CSS	Statistica/w Datasheet
CSS	Cascading Style Sheet (MIME)
CSS	Stats+ Datafile
CST	Macromedia Director "Cast" (resource) file
CSV	CompuShow Adjusted EGA/VGA Palette
CSV	Comma-separated values file
CT	A graphic file associated with the Paint Shop Pro Graphic Editor
CT	Scitex CT bitmap
CTB	AutoCAD Color-dependent Plot Style Table
CTC	PC Installer Control
CTF	Symphony Character code translation
CTL	dBase IV Control
CTL	Used in general for files containing control information. FAXWorks uses it to keep information about each fax sent and received.
CTX	Pretty Good Privacy (PGP) Ciphertext file
CTX	Microsoft Online Course Text
CTX	Visual Basic User control binary file
CUE	CDRWin (and others) Description File for a CD-Image
CUE	Microsoft Cue Cards Data
CUE	ALCATech BPM Studio Cue Points
CUL	Cursor library file (IconForge)
CUR	Windows Cursor
CURSOR	Sun Microsystems Cursor
CUT	Dr Halo Bitmap
CV	Microsoft CodeView information screen
CV	Corel Versions archive
CVG	Image
CVS	Canvas drawing file
CWK	Claris Works data
CWS	Claris Works template
CXT	Macromedia Director protected (not editable) "Cast" (resource) file
CXX	C++ source code
CZIP	Encrypted Zip File