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

CBR file extension

Comic Book RAR Archive

Compressed Files

CFM file extension

ColdFusion Markup File

Web Files

CRDOWNLOAD file extension

Chrome Partially Downloaded File

Misc Files

GAM file extension

Saved Game File

Game Files

KEY file extension

Keynote Presentation

Data Files

SDF file extension

Standard Data File

Data Files

SH file extension

Bash Shell Script

Developer Files

SITX file extension

StuffIt X Archive

Compressed Files

SWF file extension

Shockwave Flash Movie

Video Files

TARGZ file extension

Compressed Tarball File

Compressed Files

TIF file extension

Tagged Image File

Raster Image Files

TMP file extension

Temporary File

Backup Files

WPD file extension

WordPerfect Document

Text Files

YUV file extension

YUV Encoded Image File

Raster Image Files