File extensions beginning with the letter O. Commonly used extensions are listed in bold.

	O  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z .o Compiled Object File (more info) .oab Offline Address Book (more info) .ob! Orbit Downloader Incomplete Download (more info) .obj 3D Object File (more info) .obj Relocatable Object Code (more info) .obs ObjectScript Script File (more info) .oca Custom Control Library Type File (more info) .oce Open Catalog Extension Connection File (more info) .ocr FAXGrapper Fax Text File (more info) .ocx ActiveX Control (more info) .odb ABAQUS Database (more info) .odc OpenDocument Chart (more info) .odf OpenDocument Formula (more info) .odf Open Document File (more info) .odg OpenDocument Graphic (more info) .odi OpenDocument Image (more info) .odif Open Document Interchange Format (more info) .odm OverDrive Media File (more info) .odm OpenDocument Master Document (more info) .odp OpenDocument Presentation (more info) .ods OpenDocument Spreadsheet (more info) .ods Outlook Express 5 Mailbox (more info) .odt OpenDocument Text Document (more info) .odx BizTalk Server Orchestration File (more info) .oeb Outlook Express Backup Wizard File (more info) .ofc Open Financial Connectivity File (more info) .off Object File Format (more info) .ofl Ots File List (more info) .ofm OmniForm Form (more info) .oft Outlook File Template (more info) .ofx Open Financial Exchange File (more info) .oga Ogg Vorbis Audio File (more info) .ogg Ogg Vorbis Compressed Audio File (more info) .ogm Ogg Media File (more info) .ognc Dynamic Web Page (more info) .ogv Ogg Vorbis Video File (more info) .okt Oktalyzer Module (more info) .ola Online Access File (more info) .olb OLE Object Library (more info) .old Backup File (more info) .oma Sony OpenMG Music File (more info) .omcs Office Manager Access File (more info) .omf OMF Interchange Image File (more info) .omf Open Media Framework File (more info) .omg OpenMG Audio File (more info) .omo OMake Object File (more info) .omp Office Manager Document Archive (more info) .omx OtsAV Media Library Information File (more info) .ond Lotus Notes Encapsulated Memo File (more info) .one OneNote Document (more info) .oo3 OmniOutliner 3 File (more info) .opd OmniPage Document (more info) .openbsd OpenBSD Readme File (more info) .opf FlipAlbum File (more info) .opf FlipViewer FlipBook File (more info) .opml OPML File (more info) .ops Office Profile Settings File (more info) .opt Options File (more info) .opx OrgPlus Org Chart (more info) .opx FlipAlbum Photo Album File (more info) .or2 Lotus Organizer 2 File (more info) .or3 IBM Lotus Organizer 97 File (more info) .or4 IBM Lotus Organizer 97 GS File (more info) .or5 Lotus Organizer 5 File (more info) .or6 Lotus Organizer 6 File (more info) .orf Olympus RAW File (more info) .org Lotus Organizer File (more info) .ori Original File (more info) .orx RadiantOne VDS Database Schema (more info) .ost Outlook Offline Folder File (more info) .osx PowerPC Executable File (more info) .ota OTA Bitmap (more info) .otb Nokia Over The Air Bitmap (more info) .otc OpenDocument Chart Template (more info) .otf OpenTuft Tufting Design File (more info) .otf OpenType Font (more info) .otf OpenDocument Formula Template (more info) .otg OpenDocument Graphic Template (more info) .oth OpenDocument HTML Template (more info) .oti OpenDocument Image Template (more info) .otl NoteTab Outline File (more info) .otln Opal Outline File (more info) .otp OpenDocument Presentation Template (more info) .ots OtsAV Album File (more info) .ots OpenDocument Spreadsheet Template (more info) .ott OpenDocument Text Document Template (more info) .ov2 TomTom Points of Interest Database (more info) .ova Octava Musical Score (more info) .ova Open Virtual Appliance (more info) .ove Overture Musical Score (more info) .ovf Open Virtualization File (more info) .ovl Rollercoaster Tycoon 3 Sprites File (more info) .ovpn OpenVPN Configuration File (more info) .ovw Cubase WAVE File Overview (more info) .owc OutWit Catch Database (more info) .owg OutWit Gear Database (more info) .owl OWL Source Code File (more info) .owm OutWit XML Mashup File (more info) .oxt OpenOffice.org Extension (more info) .oyx Approach Alternate Database Index (more info)

All File Extensions | "O" Computer Terms

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