File extensions – definition and basic information


File extensions are the integral parts of the files that are on each computer. Often, when working on a computer, we encounter a wide range of files, such as docx, ppt, part, mp3 or rmvb. We realize that they are there – but we often do not know what they are for on our computer.

File extension, also known as the filename extension is a suffix added to the name of a computer file, usually consisting of a number of characters placed after the last dot in the filename, which gives us information about its coding. In other words a file extension is a file format. It allows the operating system (e.g. Windows) to recognize what program it should try to open the file.

In the table below you will find a random selection of popular file extensions.


File extension The full name of the file Category

AVI file extension

Audio Video Interleave File

Video Files

CFG file extension

Configuration File

Settings Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

GADGET file extension

Windows Gadget

Executable Files

GIF file extension

Graphical Interchange Format File

Raster Image Files

M4A file extension

MPEG-4 Audio File

Audio Files

MID file extension

MIDI File

Audio Files

MOBI file extension

Mobipocket eBook

eBook Files

PPT file extension

PowerPoint Presentation

Data Files

ROM file extension

N64 Game ROM File

Game Files

SDF file extension

Standard Data File

Data Files

TIF file extension

Tagged Image File

Raster Image Files

TORRENT file extension

BitTorrent File

Misc Files

WPD file extension

WordPerfect Document

Text Files

YUV file extension

YUV Encoded Image File

Raster Image Files