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

DDS file extension

DirectDraw Surface

Raster Image Files

DXF file extension

Drawing Exchange Format File

CAD Files

GAM file extension

Saved Game File

Game Files

JPG file extension

JPEG Image

Raster Image Files

JSP file extension

Java Server Page

Web Files

MP3 file extension

MP3 Audio File

Audio Files

MSI file extension

Windows Installer Package

Misc Files

PPT file extension

PowerPoint Presentation

Data Files

PY file extension

Python Script

Developer Files

RM file extension

Real Media File

Video Files

RPM file extension

Red Hat Package Manager File

Compressed Files

RSS file extension

Rich Site Summary

Web Files

RTF file extension

Rich Text Format File

Text Files

WPS file extension

Microsoft Works Word Processor Document

Text Files