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

EXE file extension

Windows Executable File

Executable Files

M4A file extension

MPEG-4 Audio File

Audio Files

SQL file extension

Structured Query Language Data File

Database Files

FLA file extension

Adobe Flash Animation

Developer Files

IBOOKS file extension

Multi-Touch iBook

Data Files

VCF file extension

vCard File

Data Files

RA file extension

Real Audio File

Audio Files

PKG file extension

Mac OS X Installer Package

Compressed Files

JAVA file extension

Java Source Code File

Developer Files

GED file extension

GEDCOM Genealogy Data File

Data Files

M3U file extension

Media Playlist File

Audio Files

RTF file extension

Rich Text Format File

Text Files

7Z file extension

7-Zip Compressed File

Compressed Files

TGA file extension

Targa Graphic

Raster Image Files

APK file extension

Android Package File

Executable Files