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

AIF file extension

Audio Interchange File Format

Audio Files

CAB file extension

Windows Cabinet File

System Files

CSV file extension

Comma Separated Values File

Data Files

DRV file extension

Device Driver

System Files

DTD file extension

Document Type Definition File

Developer Files

FLA file extension

Adobe Flash Animation

Developer Files

GBR file extension

Gerber File

Data Files

H file extension

C/C++/Objective-C Header File

Developer Files

IBOOKS file extension

Multi-Touch iBook

Data Files

JSP file extension

Java Server Page

Web Files

PLUGIN file extension

Mac OS X Plug-in

Plugin Files

PY file extension

Python Script

Developer Files

SDF file extension

Standard Data File

Data Files

TARGZ file extension

Compressed Tarball File

Compressed Files

TEX file extension

LaTeX Source Document

Text Files