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

AVI file extension

Audio Video Interleave File

Video Files

BAT file extension

DOS Batch File

Executable Files

TIFF file extension

Tagged Image File Format

Raster Image Files

H file extension

C/C++/Objective-C Header File

Developer Files

PS file extension

PostScript File

Vector Image Files

TORRENT file extension

BitTorrent File

Misc Files

DEM file extension

Video Game Demo File

Game Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

RSS file extension

Rich Site Summary

Web Files

PSD file extension

Adobe Photoshop Document

Raster Image Files

ICNS file extension

Mac OS X Icon Resource File

System Files

7Z file extension

7-Zip Compressed File

Compressed Files

TMP file extension

Temporary File

Backup Files

JAVA file extension

Java Source Code File

Developer Files

SH file extension

Bash Shell Script

Developer Files