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

CPL file extension

Windows Control Panel Item

System Files

DEM file extension

Video Game Demo File

Game Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

EXE file extension

Windows Executable File

Executable Files

KEY file extension

Keynote Presentation

Data Files

MDB file extension

Microsoft Access Database

Database Files

MPA file extension

MPEG-2 Audio File

Audio Files

PHP file extension

PHP Source Code File

Web Files

PNG file extension

Portable Network Graphic

Raster Image Files

RAR file extension

WinRAR Compressed Archive

Compressed Files

RPM file extension

Red Hat Package Manager File

Compressed Files

TGA file extension

Targa Graphic

Raster Image Files

TIFF file extension

Tagged Image File Format

Raster Image Files

TORRENT file extension

BitTorrent File

Misc Files

WPS file extension

Microsoft Works Word Processor Document

Text Files