| Extension | 描述 | 檔案格式 |
|---|
| m | Objective-C Implementation File | Developer Files |
| m1v | MPEG-1 Video File | 視頻檔案 |
| m2p | MPEG-2 File | 視頻檔案 |
| m2ts | BDAV MPEG-2 File | 視頻檔案 |
| m3d | Corel Motion Macro File | 3D Files |
| m3u | Media Playlist File | 聲音檔案 |
| m3u8 | MP3 UTF Playlist File | 文字檔 |
| m4a | Lossless Audio File | 聲音檔案 |
| m4b | MPEG-4 Audio Book File | 聲音檔案 |
| m4p | MPEG-4 Encoded Audio File | 聲音檔案 |
| m4r | iPhone Ringtone File | 聲音檔案 |
| m4v | Apple Video File | 視頻檔案 |
| maff | Mozilla Archive Format File | 壓縮檔案 |
| magnet | Vuze Magnet File | Misc Files |
| man | Unix Manual File | 文字檔 |
| manifest | Visual Styles File | 系統檔案 |
| map | Server side image map file | 網頁檔案 |
| mapimail | Send To Mail Recipient File | Misc Files |
| mar | Mozilla Archive | 壓縮檔案 |
| mar | Microsoft Access Report File | 資料檔 |
| mat | MATLAB Binary File | 資料檔 |
| mat | Microsoft Access Shortcut File | 資料檔 |
| max | 3D Studio MAX Scene File | 3D Files |
| mb | Autodesk Maya Binary Scene File | 3D Files |
| mbb | ManaBook File | 資料檔 |
| mbm | MultiBitmap files | 圖檔 |
| mbp | Mobipocket File | Misc Files |
| mca | Minecraft Anvil File | 遊戲檔案 |
| mcd | Mathcad Document File | 文件檔案 |
| mcf | Multimedia Container Format File | 視頻檔案 |
| mcl | Vectorworks Template File | 3D Files |
| mcl | Windows Media Center MCL File | 設定檔 |
| mcr | 3D Studio Max Macroscript File | 3D Files |
| mct | Musicator MIDI File | 聲音檔案 |
| md | Chaos Desktop Metadata File | 資料檔 |
| md0 | Media Descriptor Segment File | 磁碟映像檔 |
| md1 | Alcohol seperated Image FIle | 磁碟映像檔 |
| md2 | Alcohol Segment File | 磁碟映像檔 |
| md3 | Quake 3 Arena Model File | 遊戲檔案 |
| md5 | MD5 Checksum File | Misc Files |
| mdb | Microsoft Access Database File | 資料檔 |
| mde | Microsoft Access Compiled Database File | 資料檔 |
| mdf | Media Disk Image File | 磁碟映像檔 |
| mdi | Microsoft Office Document Imaging File | Layout Files |
| mdk | Keyboard Map File | Misc Files |
| mdl | Rose Model File | 資料檔 |
| mdm | Mario Dash Map File | 遊戲檔案 |
| mdm | Telix Modem Definition File | 設定檔 |
| mdmp | Windows Minidump File | 系統檔案 |
| mds | Media Descriptor File | 磁碟映像檔 |
| mdx | Database Index File | 資料檔 |
| me | Readme File | 文字檔 |
| med | RSView32 Project Development File | Misc Files |
| mem | FoxPro Memory Variable File | Developer Files |
| menc | Windows Mobile Encrypted File | 資料檔 |
| met | eMule Information File | 資料檔 |
| meta | RealPlayer Metafile | 視頻檔案 |
| metadata_never_index | Metadata Setting File | 系統檔案 |
| mf | Java Manifest File | Developer Files |
| mft | Kaspersky File | Misc Files |
| mht | MIME HTML File | 網頁檔案 |
| mid | MIDI File | 聲音檔案 |
| mif | FrameMaker Interchange Format File | 圖檔 |
| mim | MIM File | Misc Files |
| mine | Minecraft Save Game File | 遊戲檔案 |
| mir | Bauhaus Mirage Data File | 資料檔 |
| mix | Microsoft Image Exchange File | 圖檔 |
| mkv | Matroska Video File | 視頻檔案 |
| mld | Polyphonic Ringtone File | 聲音檔案 |
| mlm | Groupwise Email File | Misc Files |
| mls | Milestones Simplicity Project File | 資料檔 |
| mmb | Multimedia Builder File | Misc Files |
| mmf | Synthetic music Mobile Application Format | 聲音檔案 |
| mny | Microsoft Money Data File | 資料檔 |
| mo | Audacity language file | 3D Files |
| mobi | Mobipocket E-Book File | 資料檔 |
| mod | Camcorder Video File | 視頻檔案 |
| modd | Picture Motion Browser Data File | 視頻檔案 |
| mof | MSInfo File | 系統檔案 |
| moff | Picture Motion Browser Data File | 視頻檔案 |
| moi | MOI Video Information File | 視頻檔案 |
| mov | Apple QuickTime Movie | 視頻檔案 |
| mp | Multiplan Spreadsheet File | 試算表檔案 |
| mp3 | MPEG1/2 Audio Layer 3 | 聲音檔案 |
| mp4 | MPEG-4 | 視頻檔案 |
| mp7 | Multisim File | Misc Files |
| mpa | MPEG Audio 2 File | 聲音檔案 |
| mpb | Mipony Backup File | 備份檔案 |
| mpc | Musepack Audio File | 聲音檔案 |
| mpd | Melodyne Project Document | 聲音檔案 |
| mpd | Microsoft Project Database File | 資料檔 |
| mpeg | MPEG Movie File | 視頻檔案 |
| mpg | MPEG-1 | 視頻檔案 |
| mpl | Playlist Data File | 資料檔 |
| mpls | Mathcad Font File | 資料檔 |
| mpls | Blu-ray Information File | 視頻檔案 |
| mpo | Multi Picture Format Compatible file | 3D Files |
| mpp | Microsoft Project File | 資料檔 |
| mpq | Game Data File | 遊戲檔案 |
| mpqe | Starcraft 2 Encrypted Data File | 遊戲檔案 |
| mps | Pocket Streets Map File | Geographical Files |
| mps | Max Payne Saved Game File | 遊戲檔案 |
| mptm | OpenMPT Module | 聲音檔案 |
| mq4 | MetaTrader Indicator File | Misc Files |
| mrc | MRC Image File | Misc Files |
| mrk | Digital Print Order Format File | Misc Files |
| mrt.exe._p | Malicious Software Removal Tool File | Misc Files |
| msf | Email Summary File | Misc Files |
| msg | Encapsulated Email Message | 文字檔 |
| msi | Windows Installer File | Misc Files |
| msmessagestore | Windows Live Mail Message Information Database File | Misc Files |
| msn | MSN Content Plus File | Misc Files |
| mso | Word OLE Web Page Storage Stream File | Misc Files |
| mssign | Digital Signature File | 加密檔案 |
| mst | Windows Installer Transform File | 系統檔案 |
| msu | Windows Update File | Misc Files |
| mswmm | Windows Movie Maker Project | 視頻檔案 |
| mta | AllShare Metadate File | 資料檔 |
| mtf | Motorola Theme File | Misc Files |
| mts | AVCHD Video File | 視頻檔案 |
| mtv | MTV Video File | 視頻檔案 |
| mui | Multilingual Resource File | 系統檔案 |
| mus | PlayStation 2 Music File | 遊戲檔案 |
| mxc2 | Magix Musicmaker Cache File | 系統檔案 |
| mxdl | Maxthon Partially Downloaded File | 網頁檔案 |
| mxf | Material Exchange Format File | 視頻檔案 |
| mxl | PackRat File | Misc Files |
| mxl | Moxcel Spreadsheet File | 試算表檔案 |
| mxm | Magix Multimedia File | 多媒體檔案 |
| mxv | MAGIX Movie Edit Pro File | 視頻檔案 |
| myr | Mryiad Document File | 聲音檔案 |
| mzp | Mozart Percussion File | 3D Files |
| mzp | Maxscript Compressed File | 3D Files |