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

AIF file extension

Audio Interchange File Format

Audio Files

MID file extension

MIDI File

Audio Files

GAM file extension

Saved Game File

Game Files

C file extension

C/C++ Source Code File

Developer Files

XLS file extension

Excel Spreadsheet

Spreadsheet Files

KML file extension

Keyhole Markup Language File

GIS Files

WMA file extension

Windows Media Audio File

Audio Files

EXE file extension

Windows Executable File

Executable Files

SLN file extension

Visual Studio Solution File

Developer Files

PNG file extension

Portable Network Graphic

Raster Image Files

JSP file extension

Java Server Page

Web Files

TGA file extension

Targa Graphic

Raster Image Files

7Z file extension

7-Zip Compressed File

Compressed Files

LUA file extension

Lua Source File

Developer Files

EPS file extension

Encapsulated PostScript File

Vector Image Files