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

AZW file extension

Amazon Kindle eBook File

eBook Files

C file extension

C/C++ Source Code File

Developer Files

CAB file extension

Windows Cabinet File

System Files

DEM file extension

Video Game Demo File

Game Files

DXF file extension

Drawing Exchange Format File

CAD Files

GED file extension

GEDCOM Genealogy Data File

Data Files

HQX file extension

BinHex 4.0 Encoded File

Encoded Files

KMZ file extension

Google Earth Placemark File

GIS Files

MPA file extension

MPEG-2 Audio File

Audio Files

PSPIMAGE file extension

PaintShop Pro Image

Raster Image Files

ROM file extension

N64 Game ROM File

Game Files

RPM file extension

Red Hat Package Manager File

Compressed Files

TAX2012 file extension

TurboTax 2012 Tax Return

Data Files

VCF file extension

vCard File

Data Files

3GP file extension

3GPP Multimedia File

Video Files