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

CFM file extension

ColdFusion Markup File

Web Files

EPUB file extension

Open eBook File

eBook Files

GADGET file extension

Windows Gadget

Executable Files

GAM file extension

Saved Game File

Game Files

LNK file extension

Windows File Shortcut

System Files

M4A file extension

MPEG-4 Audio File

Audio Files

MSG file extension

Outlook Mail Message

Text Files

MSI file extension

Windows Installer Package

Misc Files

PAGES file extension

Pages Document

Text Files

PPT file extension

PowerPoint Presentation

Data Files

PY file extension

Python Script

Developer Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

TEX file extension

LaTeX Source Document

Text Files

3DS file extension

3D Studio Scene

3D Image Files

3GP file extension

3GPP Multimedia File

Video Files