| O | Compiled Object File | Developer Files | 2 | 1 |
| O1 | Object File For GO321v1 Platform | Data Files | 1 | 1 |
| O2C | Objects To See 3D File Format | Graphic Files | 1 | 1 |
| O3 | Ozone Messenger Program Support Files |
Data Files
| 1 | 1 |
| O3D | Google Open 3D Web Graphic Format |
Graphic Files
| 1 | 1 |
| OAB | Offline Address Book |
Data Files
| 1 | 1 |
| OAD | Suite Notaro Document |
Data Files
| 1 | 1 |
| OAF | ETH Oberon Applet |
Data Files
| 1 | 1 |
| OAP | Samsung Bada Signed Installation Package | Compressed Files | 2 | 2 |
| OAS | Fujitsu OAS Document File | Text Files | 2 | 2 |
| OB | Orbit Downloader Incomplete Download | Uncommon Files | 3 | 3 |
| OB! | Orbit Downloader Incomplete Download |
Uncommon Files
| 1 | 1 |
| OB1 | OzWin CompuServe E-mail/Forum Access Saved Outbox File |
Data Files
| 1 | 1 |
| OBB | Android Opaque Binary Blob File |
Data Files
| 1 | 1 |
| OBD | Office Binder Document |
Data Files
| 1 | 1 |
| OBE | Objeck Executable File |
Developer Files
| 1 | 1 |
| OBI | Outlook RSS Subscription File | Settings Files | 1 | 1 |
| OBJ | Wavefront 3D Object File | 3D Image Files | 11 | 1 |
| OBK | DiskImage Backup File | Backup Files | 2 | 2 |
| OBML | Opera Mini Saved Web Page | Web Files | 2 | 1 |
| OBML16 | Opera Mini Saved Web Page |
Web Files
| 2 | 1 |
| OBP | Bryce Object File |
3D Image Files
| 1 | 1 |
| OBR | Borland C++ Object Browser Data |
Developer Files
| 4 | 2 |
| OBS | WAsP Obstacle List Data |
Data Files
| 3 | 3 |
| OBT | Openbox Theme File |
Settings Files
| 2 | 2 |
| OBV | 3D Photo Browser Thumbnail Cache |
Data Files
| 1 | 1 |
| OBW | Superior Drummer Sounds File | Audio Files | 1 | 1 |
| OBZ | Compressed 3D Object File |
3D Image Files
| 1 | 1 |
| OC8 | OrgCon Organization File |
Data Files
| 1 | 1 |
| OC9 | OrgCon Organization File |
Data Files
| 1 | 1 |
| OCA | Custom Control Library Type File |
Developer Files
| 1 | 1 |
| OCB | Origin Precompiled Origin C Source Code |
Developer Files
| 1 | 1 |
| OCC | Oceanic DataPool File |
Data Files
| 2 | 2 |
| OCD | OCAD Map File | GIS Files | 3 | 3 |
| OCDF | OneClickDigital MP3 Audio Book |
Audio Files
| 1 | 1 |
| OCE | Open Catalog Extension Connection File |
Settings Files
| 1 | 1 |
| OCH | Satellite And Channel Settings Backup |
Backup Files
| 1 | 1 |
| OCI | OpenCanvas Image | Raster Image Files | 1 | 1 |
| OCIMF | OCIMF HVPQ File |
Data Files
| 1 | 1 |
| OCN | OneCable.net - Explorer Measurement Data File |
Data Files
| 1 | 1 |
| OCP | Offline Commander Project File |
Data Files
| 2 | 2 |
| OCR | Subtitle Workshop OCR Script |
Uncommon Files
| 5 | 2 |
| OCS | eDoc DigiSign Digitally Signed Document |
Data Files
| 1 | 1 |
| OCSMEET | Microsoft Lync Data |
Data Files
| 1 | 1 |
| OCSP | HAProxy OCSP Data File |
Data Files
| 1 | 1 |
| OCT | Radiance Octree File |
3D Image Files
| 1 | 1 |
| OCTEST | Xcode Objective-C Unit Test Bundle |
Developer Files
| 1 | 1 |
| OCV | OCV Training Data |
Data Files
| 1 | 1 |
| OCW | Symantec ESM Oracle Configuration Watch Template File |
Data Files
| 1 | 1 |
| OCX | ActiveX Control |
Developer Files
| 1 | 1 |
| OC_ | Compressed ActiveX Control File |
Compressed Files
| 1 | 1 |
| OD1 | Omnis 5 Database |
Data Files
| 1 | 1 |
| OD4 | Omnis5 Database File | Database Files | 1 | 1 |
| OD5 | Omnis 5 Database |
Data Files
| 1 | 1 |
| OD9 | Omnis5 Database File |
Database Files
| 1 | 1 |
| ODB | OpenDocument Database |
Database Files
| 6 | 3 |
| ODC | Office Data Connection File |
Settings Files
| 6 | 2 |
| ODCCUBEFILE | OpenDocument 1 Chart |
Uncommon Files
| 1 | 1 |
| ODCDATABASEFILE | Microsoft Office File |
Data Files
| 1 | 1 |
| ODCTABLECOLLECTIONFILE | Microsoft Office Component |
Data Files
| 1 | 1 |
| ODCTABLEFILE | Microsoft Office File |
Data Files
| 1 | 1 |
| ODD | Coby Voice Recorder Data |
Audio Files
| 2 | 2 |
| ODF | OpenDocument Formula |
Uncommon Files
| 13 | 4 |
| ODG | OpenDocument Graphic File | Vector Image Files | 5 | 2 |
| ODI | OpenDocument Image |
Raster Image Files
| 2 | 1 |
| ODIF | Open Document Interchange Format |
Text Files
| 1 | 1 |
| ODK | Uncommon File Extension |
Uncommon Files
| 1 | 1 |
| ODL | Object Description Language File |
Developer Files
| 1 | 1 |
| ODM | OpenDocument Master Document |
Text Files
| 6 | 2 |
| ODP | OpenDocument Presentation |
Data Files
| 3 | 1 |
| ODR | OpenIV Model Data |
Data Files
| 2 | 2 |
| ODS | OpenDocument Spreadsheet | Spreadsheet Files | 5 | 1 |
| ODT | OpenDocument Text Document |
Text Files
| 13 | 3 |
| ODTX | Unknown File Type |
Uncommon Files
| 1 | 1 |
| ODV | Ocean Data View Data |
Data Files
| 1 | 1 |
| ODZ | IBM OpenDoc Editor Package |
Data Files
| 1 | 1 |
| OEACCOUNT | Windows Mail Account File |
Data Files
| 1 | 1 |
| OEB | Open eBook File | eBook Files | 19 | 2 |
| OEC | OE-Cake File |
Data Files
| 1 | 1 |
| OED | Uncommon File Extension |
Uncommon Files
| 1 | 1 |
| OEM | Original Equipment Manufacturer Setup File |
Settings Files
| 2 | 2 |
| OF | Unknown File Type |
Uncommon Files
| 1 | 1 |
| OFB | Oxygen Forensic Suite Backup |
Backup Files
| 1 | 1 |
| OFC | Open Financial Connectivity File |
Data Files
| 2 | 1 |
| OFD | ObjectView Form Definition Data |
Settings Files
| 3 | 3 |
| OFE | 3D Boat Design File | CAD Files | 1 | 1 |
| OFF | Object File Format |
3D Image Files
| 2 | 1 |
| OFFICEUI | Microsoft Office UI Customization File |
Settings Files
| 1 | 1 |
| OFL | OtsTurntables Playlist |
Settings Files
| 1 | 1 |
| OFL_EN | Unknown File Type |
Uncommon Files
| 1 | 1 |
| OFM | OmniForm Form |
Data Files
| 4 | 3 |
| OFN | Systems Management Server Offer Creation Notification File |
Data Files
| 1 | 1 |
| OFS | OptimFROG Dualstream Data |
Audio Files
| 1 | 1 |
| OFT | Outlook File Template |
Data Files
| 1 | 1 |
| OFX | Open Financial Exchange File |
Data Files
| 6 | 1 |
| OGA | Ogg Vorbis Audio File |
Audio Files
| 5 | 1 |
| OGF | S.T.A.L.K.E.R. Model File |
3D Image Files
| 1 | 1 |
| OGF2 | MapViewGPS Map Coordinates File |
Data Files
| 1 | 1 |
| OGG | Ogg Vorbis Audio File |
Audio Files
| 5 | 1 |
| OGM | Ogg Media File | Video Files | 4 | 2 |
of 3 
Blog
Facebook
Twitter
Newsletter
