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

GAM file extension

Saved Game File

Game Files

TEX file extension

LaTeX Source Document

Text Files

DRV file extension

Device Driver

System Files

OTF file extension

OpenType Font

Font Files

7Z file extension

7-Zip Compressed File

Compressed Files

VCXPROJ file extension

Visual C++ Project

Developer Files

CPP file extension

C++ Source Code File

Developer Files

DDS file extension

DirectDraw Surface

Raster Image Files

PHP file extension

PHP Source Code File

Web Files

CUR file extension

Windows Cursor

System Files

M4A file extension

MPEG-4 Audio File

Audio Files

FNT file extension

Windows Font File

Font Files

MDF file extension

Media Disc Image File

Disk Image Files

DEM file extension

Video Game Demo File

Game Files

CPL file extension

Windows Control Panel Item

System Files