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

UUE file extension

Uuencoded File

Encoded Files

HTML file extension

Hypertext Markup Language File

Web Files

GIF file extension

Graphical Interchange Format File

Raster Image Files

CPL file extension

Windows Control Panel Item

System Files

7Z file extension

7-Zip Compressed File

Compressed Files

GAM file extension

Saved Game File

Game Files

TIFF file extension

Tagged Image File Format

Raster Image Files

MP4 file extension

MPEG-4 Video File

Video Files

TIF file extension

Tagged Image File

Raster Image Files

WMA file extension

Windows Media Audio File

Audio Files

DMP file extension

Windows Memory Dump

System Files

FON file extension

Generic Font File

Font Files

DXF file extension

Drawing Exchange Format File

CAD Files

SRT file extension

SubRip Subtitle File

Video Files

WMV file extension

Windows Media Video File

Video Files