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

C file extension

C/C++ Source Code File

Developer Files

CFM file extension

ColdFusion Markup File

Web Files

CRX file extension

Chrome Extension

Plugin Files

DBF file extension

Database File

Database Files

DEB file extension

Debian Software Package

Compressed Files

DRV file extension

Device Driver

System Files

FLA file extension

Adobe Flash Animation

Developer Files

MIM file extension

Multi-Purpose Internet Mail Message File

Encoded Files

PL file extension

Perl Script

Developer Files

PLUGIN file extension

Mac OS X Plug-in

Plugin Files

RM file extension

Real Media File

Video Files

RTF file extension

Rich Text Format File

Text Files

SAV file extension

Saved Game

Game Files

UUE file extension

Uuencoded File

Encoded Files

XML file extension

XML File

Data Files