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

FLA file extension

Adobe Flash Animation

Developer Files

JSP file extension

Java Server Page

Web Files

CPL file extension

Windows Control Panel Item

System Files

AIF file extension

Audio Interchange File Format

Audio Files

ISO file extension

Disc Image File

Disk Image Files

CER file extension

Internet Security Certificate

Web Files

RAR file extension

WinRAR Compressed Archive

Compressed Files

SH file extension

Bash Shell Script

Developer Files

RA file extension

Real Audio File

Audio Files

ROM file extension

N64 Game ROM File

Game Files

7Z file extension

7-Zip Compressed File

Compressed Files

TIFF file extension

Tagged Image File Format

Raster Image Files

KML file extension

Keyhole Markup Language File

GIS Files

SRT file extension

SubRip Subtitle File

Video Files

INI file extension

Windows Initialization File

Settings Files