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

ACCDB file extension

Access 2007 Database File

Database Files

BAT file extension

DOS Batch File

Executable Files

DMG file extension

Mac OS X Disk Image

Disk Image Files

DMP file extension

Windows Memory Dump

System Files

DRV file extension

Device Driver

System Files

GED file extension

GEDCOM Genealogy Data File

Data Files

GIF file extension

Graphical Interchange Format File

Raster Image Files

IBOOKS file extension

Multi-Touch iBook

Data Files

LNK file extension

Windows File Shortcut

System Files

PS file extension

PostScript File

Vector Image Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

WMV file extension

Windows Media Video File

Video Files

YUV file extension

YUV Encoded Image File

Raster Image Files

ZIPX file extension

Extended Zip File

Compressed Files

3DS file extension

3D Studio Scene

3D Image Files