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

ASX file extension

Microsoft ASF Redirector File

Video Files

CRX file extension

Chrome Extension

Plugin Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

GADGET file extension

Windows Gadget

Executable Files

GED file extension

GEDCOM Genealogy Data File

Data Files

GPX file extension

GPS Exchange File

GIS Files

JS file extension

JavaScript File

Web Files

PDF file extension

Portable Document Format File

Layout Files

PIF file extension

Program Information File

Executable Files

RPM file extension

Red Hat Package Manager File

Compressed Files

SRT file extension

SubRip Subtitle File

Video Files

SYS file extension

Windows System File

System Files

TARGZ file extension

Compressed Tarball File

Compressed Files

XCODEPROJ file extension

Xcode Project

Developer Files

YUV file extension

YUV Encoded Image File

Raster Image Files