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

FLV file extension

Flash Video File

Video Files

IBOOKS file extension

Multi-Touch iBook

Data Files

M3U file extension

Media Playlist File

Audio Files

OTF file extension

OpenType Font

Font Files

PSD file extension

Adobe Photoshop Document

Raster Image Files

RA file extension

Real Audio File

Audio Files

RPM file extension

Red Hat Package Manager File

Compressed Files

SAV file extension

Saved Game

Game Files

SITX file extension

StuffIt X Archive

Compressed Files

TMP file extension

Temporary File

Backup Files

VCF file extension

vCard File

Data Files

ZIP file extension

Zipped File

Compressed Files

3G2 file extension

3GPP2 Multimedia File

Video Files