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

AI file extension

Adobe Illustrator File

Vector Image Files

APP file extension

Mac OS X Application

Executable Files

CFG file extension

Configuration File

Settings Files

CRDOWNLOAD file extension

Chrome Partially Downloaded File

Misc Files

GIF file extension

Graphical Interchange Format File

Raster Image Files

HTML file extension

Hypertext Markup Language File

Web Files

JS file extension

JavaScript File

Web Files

M4V file extension

iTunes Video File

Video Files

PHP file extension

PHP Source Code File

Web Files

PPT file extension

PowerPoint Presentation

Data Files

RPM file extension

Red Hat Package Manager File

Compressed Files

SH file extension

Bash Shell Script

Developer Files

VCD file extension

Virtual CD

Disk Image Files

VCXPROJ file extension

Visual C++ Project

Developer Files

WMA file extension

Windows Media Audio File

Audio Files