Alphabetically: C
Extension File Description File Type
.c
C/C++ Source Code File
Developer
.c00
WinAce Split Archive File
Compressed
.c01
WinAce Split Archive Part 1 File
Compressed
.c02
WinAce Split Archive Part 1 File
Compressed
.c2d
WinOnCD Disc Image
Disk Image
.c2r
Windows Media Center Click-To-Record File
Settings
.c4
JEDMICS Image File
Raster Image
.c4d
Cinema 4D Model File
3D Image
.c4k
Clonk Key File
Game
.ca
Initial Telnet Cache
Misc
.cab
Windows Cabinet File
System
.cache
Cache File
Misc
.cad
BobCAD-CAM File
CAD
.caf
Core Audio File
Audio
.cag
ClipArt Gallery Package
Vector Image
.cal
Calendar File
Layout
.calb
Coolect Album File
Misc
.cals
CALS Raster Graphic File
Raster Image
.cam
Gerber CAM Job File
CAD
.camp
WCS Color Appearance Model Profile File
Settings
.camproj
Camtasia Studio Project
Video
.camrec
Camtasia Studio Screen Recording
Video
.can
Canon Navigator Fax Document
Raster Image
.cap
Construct Game Development File
Developer
.car
Brew Component Application Resource File
Developer
.carc
Nintendo DS Compressed Archive File
Game
.cat
Advanced Disk Catalog Database
Database
.catpart
CATIA V5 Part File
CAD
.catproduct
CATIA V5 Assembly File
CAD
.cav
Comodo Virus Definitions File
Data
.cb7
Comic Book 7-Zip Archive
Compressed
.cbds
Comic Book DS File
Misc
.cbf
Calendar Builder File
Layout
.cbg
CyberGauge Data File
Data
.cbk
Backup Configuration File
Backup
.cbl
COBOL Program File
Developer
.cbr
Comic Book RAR Archive
Compressed
.cbs
Code Breaker PS2 Save File
Game
.cbt
Computer Based Training File
Misc
.cbz
Comic Book ZIP Archive
Compressed
.cc
C++ Source Code File
Developer
.ccd
CloneCD Disk Image
Disk Image
.ccf
CryptLoad Container File
Encoded
.cch
Corel Chart File
Data
.ccn
Compressed Multimedia Fusion File
Developer
.ccp
RIB Import Converter Profile
Data
.ccr
ASTM Continuity of Care Record
Data
.ccscc
ClearCase Source Control Info File
Developer
.cct
Director Protected Cast Resource
Data
.ccx
Click & Create Extension
Plugin
.cd
Visual Studio Class Diagram
Developer
.cd2
Click'N Design 3d File
Layout
.cd5
Chasys Draw Image File
Raster Image
.cda
CD Audio Track Shortcut
Audio
.cdb
Symbian Phonebook Database
Database
.cdc
AutoCAD DesignCenter Preview Cache File
Raster Image
.cdd
ConceptDraw PRO Document
Vector Image
.cdda
CD Digital Audio File
Audio
.cdf
Content Definition File
Data
.cdg
Compact Disc Plus Graphics Image
Raster Image
.cdi
DiscJuggler Disc Image
Disk Image
.cdl
CADKEY Wireframe Design File
CAD
.cdmm
ConceptDraw MINDMAP Document
Vector Image
.cdmp
WCS Device Model Profile
System
.cdmt
ConceptDraw MINDMAP Template
Vector Image
.cdmtz
Compressed ConceptDraw MINDMAP Template
Vector Image
.cdmz
Compressed ConceptDraw MINDMAP Document
Vector Image
.cdp
Trainz Simulator Content Dispatcher Pack
Game
.cdp2
Trainz Classics Content Dispatcher Pack 2
Game
.cdr
CorelDRAW Image File
Vector Image
.cdt
CorelDRAW Image Template
Settings
.cdx
Compound Index File
Data
.ce
ComputerEyes Image
Raster Image
.ceb
Apabi eBook File
Misc
.cedprj
Ashampoo CoverEditor Project
Layout
.cel
Audition Loop
Audio
.celtx
Celtx Project File
Data
.cer
Internet Security Certificate
Web
.cfa
Adobe Conformed Audio File
Audio
.cfc
ColdFusion Component File
Developer
.cfg
Configuration File
Settings
.cfge
Jewel Quest Configuration File
Game
.cfl
IMVU Product File
Misc
.cfm
ColdFusion Markup File
Web
.cfml
ColdFusion Markup Language File
Web
.cfr
Cross Fire Replay File
Game
.cfs
Compact File Set Archive
Disk Image
.cgf
Far Cry Model File
Game
.cgi
Common Gateway Interface Script
Executable
.cgm
Computer Graphics Metafile
Vector Image
.cgp
PixelCryptor Encrypted File
Encoded
.cgr
Quest3D Channel Group File
Settings
.cgz
Linux Drivers Archive
System
.ch3
Harvard Graphics DOS Chart File
Layout
.cha
Online Chat Configuration File
Web
.charset
Character Set
Text
.chat
Online Chat Configuration File
Web
.chd
MAME Hard Disk Image
Game
.chef
Chef Source Code File
Developer
.chg
Quicken Online Data File
Data
.chk
Saved File Fragment
Misc
.chl
WinFast PVR2 Channel List
Settings
.chm
Compiled HTML Help File
Web
.chml
Chameleon Encrypted Database File
Encoded
.chn
Ethnograph Data
Data
.chord
Song Chords File
Text
.chr
3ds Max Characters File
3D Image
.cht
SNES Cheat File
Game
.chw
Compiled Help Index File
Misc
.chx
AutoCAD Standards Check File
Settings
.cidb
iTunes CD Information File
Audio
.cif
Easy CD Creator Disk Image
Disk Image
.cil
ClipArt Gallery Packaged File
Vector Image
.cimg
CImg Image File
Raster Image
.cin
Kodak Cineon Bitmap File
Raster Image
.cit
Intergraph Bitmap Image File
Raster Image
.ck9
Cook'n Cookbook Backup File
Backup
.ckd
Kubotek Design Container
CAD
.ckt
CircuitMaker File
Data
.cl2
HY-TEK Meet Results File
Data
.cl4
Easy CD Creator 4 Project File
Data
.cl5
Easy CD Creator 5 Saved Project
Disk Image
.class
Java Class File
Developer
.classlist
SMART Notebook Class List File
Data
.clb
COM+ Catalog File
System
.cld
Canon CD Label Template
Layout
.clg
Windows Catalog File
Settings
.clix
CLIX Command File
Data
.clk
Corel R.A.V.E Project File
Data
.clkk
Clicker Keyboard
Misc
.clkt
Clicker Template
Misc
.clkw
Clicker Word Bank
Misc
.clkx
Clicker Grid Set
Misc
.clm
MagicJack Call Log File
Data
.clp
Windows Clipboard File
Data
.clpi
Blu-ray Clip Information File
Video
.clr
Flash Color Set
Misc
.cls
LaTeX Document Class File
Misc
.clx
Standard Dictionary File
Data
.cm
CLEO Custom Mission
Game
.cm2
Poser Camera Set File
3D Image
.cmbl
Logger Pro Data File
Data
.cmd
Windows Command File
Executable
.cmf
Creative Music Format
Audio
.cml
Chemical Markup Language File
Data
.cmm
Corel Multimedia Manager Album
Misc
.cmmp
Camtasia MenuMaker Project
Video
.cmmtpl
Camtasia MenuMaker Template
Video
.cmp
Solid Edge Wire Harness File
CAD
.cmproj
Camtasia Project File
Video
.cmrec
Camtasia Recording
Video
.cms
Content Management System
Web
.cmx
Corel Metafile Exchange Image File
Vector Image
.cmz
Compressed Poser Camera Set File
3D Image
.cn1
CNR Modem Initialization Data File
Data
.cna
Catena Project File
Data
.cnc
CNC Machine Tool Path
CAD
.cnf
Telnet Configuration File
Settings
.cnt
Help Contents File
System
.cnv
Canvas 6-8 Drawing File
Vector Image
.cob
COBOL Source Code File
Developer
.cod
Compiled Source Code
Developer
.col
Grand Theft Auto Collision File
Game
.collection
Adobe Bridge Collection File
Data
.colorpicker
Color Picker Plugin
Plugin
.com
DOS Command File
Executable
.comicdoc
Comic Life Document
Layout
.component
Mac OS X System Component
Plugin
.compositefont
Windows Composite Font File
Font
.con
Concept Application Source File
Web
.conf
Unix Configuration File
Settings
.config
Configuration File
Developer
.contact
Windows Contact File
Data
.contour
Contour Screenplay File
Misc
.copy
Sony Ericsson Protected Content File
Audio
.cor
Trimble Corrected SSF File
Data
.cos2
Pinnacle Studio Cache File
Misc
.cox
Click & Create Extension
Plugin
.cp
Xcode C++ Source File
Developer
.cp3
Grand Prix 3 Cockpit Shape File
Misc
.cp9
ChoicePoint Encrypted File
Compressed
.cpa
CADSTAR PCB Archive File
CAD
.cpc
CPC Compressed Image File
Raster Image
.cpd
Compressed PhotoDefiner Image File
Raster Image
.cpg
Manga Studio Page File
Raster Image
.cpgz
Compressed CPIO Archive
Compressed
.cph
Corel Print House File
Layout
.cpi
AVCHD Video Clip Information File
Video
.cpio
Unix CPIO Archive
Encoded
.cpl
Windows Control Panel Item
System
.cpmz
Miradi/ConPro Project File
Data
.cpn
Age of Mythology Campaign File
Game
.cpp
C++ Source Code File
Developer
.cpr
Cubase Project
Audio
.cps
Corel Photo House File
Raster Image
.cpt
Corel Photo-Paint Document
Raster Image
.cptl
Adobe Captivate Project Template File
Data
.cptx
Adobe Captivate Project File
Data
.cpx
Oracle ADF Binding Context File
Settings
.cpy
eCopy Desktop File
Layout
.cr2
Canon Raw Image File
Raster Image
.crash
Mac OS X Crash Log File
System
.crashed
AbiWord Crash-Saved Document
Misc
.crc
Total Commander Checksum File
Misc
.crd
Windows CardSpace File
Misc
.crdownload
Chrome Partially Downloaded File
Web
.crds
Windows CardSpace Backup File
Backup
.crev
Adobe Captivate Commentable SWF File
Data
.crs
StepMania Course File
Game
.crt
Security Certificate
Web
.crtx
Office 2007 Chart Template File
Data
.crw
Canon Raw CIFF Image File
Raster Image
.crwl
Windows Crawl File
Text
.crx
Chrome Extension
Plugin
.cry
CryENGINE Map File
Data
.crz
Compressed Poser Character Rigging File
3D Image
.cs
Visual C# Source Code File
Developer
.csa
PNA Code Calset File
Data
.csd
Compact Shared Document
Layout
.csf
Content Secure Format
Raster Image
.csh
Photoshop Custom Shapes File
Misc
.csi
ContentServ Include File
Developer
.csm
Character Studio Marker File
3D Image
.csn
Adobe Code Snippet Document
Developer
.cso
Compressed ISO Disk Image
Disk Image
.csp
Concept Server Page
Web
.csproj
Visual Studio C# Project
Developer
.csr
Certificate Signing Request File
Web
.css
Cascading Style Sheet
Web
.cst
ContentServ Template
Developer
.csv
Comma Separated Values File
Data
.csy
Canvas Symbol File
Vector Image
.ct
Cheat Engine Cheat Table
Game
.ctb
AutoCAD Color-Based Plot Style File
Settings
.ctf
AVG Update Control File
Misc
.ctg
Canon Digital Camera Catalog File
Misc
.ctl
Visual Basic UserControl Object File
Developer
.ctm
CrazyTalk Model File
Data
.ctp
CakePHP Template
Developer
.ctt
Messenger Contact List
Data
.ctx
Visual Basic Control Binary File
Developer
.cty
SimCity City File
Game
.cue
Cue Sheet File
Disk Image
.cui
Autodesk Custom Workspace File
Settings
.cuix
AutoCAD Custom User Interface File
Settings
.cul
Windows Cursor Library
Misc
.cur
Windows Cursor
System
.cursorfx
CursorFX Theme File
Data
.curxptheme
CursorXP Theme File
Data
.cus
AutoCAD Custom Dictionary File
Settings
.cut
Dr. Halo Bitmap Image File
Raster Image
.cv5
Canvas 5 Drawing File
Vector Image
.cva
HP Systems Software Manager Information File
Settings
.cvc
cVideo
Video
.cvd
ClamAV Virus Definitions File
Data
.cvf
CPU-Z Validation File
Misc
.cvg
Calamus Vector Graphic File
Vector Image
.cvi
Canvas Image Format
Vector Image
.cvn
CineVision Encoding Session
Data
.cvs
Canvas 3 Drawing File
Vector Image
.cvt
Canvas External Tool File
Plugin
.cvx
Canvas Drawing File
Vector Image
.cwf
CorelDRAW Workspace File
Settings
.cwk
ClarisWorks Document
Data
.cwp
Cakewalk SONAR Project
Audio
.cws
Claris Works Template
Text
.cwz
Circuit Wizard File
Data
.cxt
Director Protected Cast File
Data
.cxx
C++ Source Code File
Developer
.cyi
Clustify Input File
Text
.cyo
Clustify Output File
Data
.cys
Clustify Summary File
Data
.cyw
Rbot.CYW Worm File
Executable