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

PHP file extension

PHP Source Code File

Web Files

PIF file extension

Program Information File

Executable Files

TARGZ file extension

Compressed Tarball File

Compressed Files

AIF file extension

Audio Interchange File Format

Audio Files

MID file extension

MIDI File

Audio Files

XML file extension

XML File

Data Files

GAM file extension

Saved Game File

Game Files

DNG file extension

Digital Negative Image File

Camera Raw Files

DDS file extension

DirectDraw Surface

Raster Image Files

PNG file extension

Portable Network Graphic

Raster Image Files

JAR file extension

Java Archive File

Executable Files

MAX file extension

3ds Max Scene File

3D Image Files

VCF file extension

vCard File

Data Files

7Z file extension

7-Zip Compressed File

Compressed Files

MSI file extension

Windows Installer Package

Misc Files