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

AZW file extension

Amazon Kindle eBook File

eBook Files

DMP file extension

Windows Memory Dump

System Files

MSI file extension

Windows Installer Package

Misc Files

OBJ file extension

Wavefront 3D Object File

3D Image Files

OTF file extension

OpenType Font

Font Files

PPTX file extension

PowerPoint Open XML Presentation

Data Files

RAR file extension

WinRAR Compressed Archive

Compressed Files

ROM file extension

N64 Game ROM File

Game Files

TAR file extension

Consolidated Unix File Archive

Data Files

TEX file extension

LaTeX Source Document

Text Files

VB file extension

VBScript File

Executable Files

VCXPROJ file extension

Visual C++ Project

Developer Files

WPD file extension

WordPerfect Document

Text Files

3DM file extension

Rhino 3D Model

3D Image Files

3DS file extension

3D Studio Scene

3D Image Files