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

C file extension

C/C++ Source Code File

Developer Files

CSV file extension

Comma Separated Values File

Data Files

DESKTHEMEPACK file extension

Windows 8 Desktop Theme Pack File

System Files

DRV file extension

Device Driver

System Files

EPUB file extension

Open eBook File

eBook Files

GPX file extension

GPS Exchange File

GIS Files

ICS file extension

iCalendar File

Misc Files

M4A file extension

MPEG-4 Audio File

Audio Files

MDB file extension

Microsoft Access Database

Database Files

RM file extension

Real Media File

Video Files

SAV file extension

Saved Game

Game Files

TGA file extension

Targa Graphic

Raster Image Files

WAV file extension

WAVE Audio File

Audio Files

WPS file extension

Microsoft Works Word Processor Document

Text Files

XLR file extension

Works Spreadsheet

Spreadsheet Files