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

ASX file extension

Microsoft ASF Redirector File

Video Files

BAT file extension

DOS Batch File

Executable Files

BIN file extension

Binary Disc Image

Disk Image Files

DAT file extension

Data File

Data Files

EXE file extension

Windows Executable File

Executable Files

IBOOKS file extension

Multi-Touch iBook

Data Files

M4V file extension

iTunes Video File

Video Files

MPG file extension

MPEG Video File

Video Files

PPS file extension

PowerPoint Slide Show

Data Files

RA file extension

Real Audio File

Audio Files

RM file extension

Real Media File

Video Files

SWF file extension

Shockwave Flash Movie

Video Files

WPS file extension

Microsoft Works Word Processor Document

Text Files

3GP file extension

3GPP Multimedia File

Video Files