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

ACCDB file extension

Access 2007 Database File

Database Files

ASPX file extension

Active Server Page Extended File

Web Files

ASX file extension

Microsoft ASF Redirector File

Video Files

FLA file extension

Adobe Flash Animation

Developer Files

FLV file extension

Flash Video File

Video Files

GPX file extension

GPS Exchange File

GIS Files

GZ file extension

Gnu Zipped Archive

Compressed Files

ICS file extension

iCalendar File

Misc Files

ISO file extension

Disc Image File

Disk Image Files

NES file extension

Nintendo (NES) ROM File

Game Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

SWF file extension

Shockwave Flash Movie

Video Files

TGA file extension

Targa Graphic

Raster Image Files

WSF file extension

Windows Script File

Executable Files

XCODEPROJ file extension

Xcode Project

Developer Files