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

ASX file extension

Microsoft ASF Redirector File

Video Files

CRX file extension

Chrome Extension

Plugin Files

DOC# file extension

Microsoft Word Document

Text Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

GBR file extension

Gerber File

Data Files

LNK file extension

Windows File Shortcut

System Files

M file extension

Objective-C Implementation File

Developer Files

MIM file extension

Multi-Purpose Internet Mail Message File

Encoded Files

MSI file extension

Windows Installer Package

Misc Files

NES file extension

Nintendo (NES) ROM File

Game Files

PHP file extension

PHP Source Code File

Web Files

PS file extension

PostScript File

Vector Image Files

PSD file extension

Adobe Photoshop Document

Raster Image Files

SYS file extension

Windows System File

System Files

VCF file extension

vCard File

Data Files