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

FLV file extension

Flash Video File

Video Files

XLS file extension

Excel Spreadsheet

Spreadsheet Files

RA file extension

Real Audio File

Audio Files

NES file extension

Nintendo (NES) ROM File

Game Files

JPG file extension

JPEG Image

Raster Image Files

TGA file extension

Targa Graphic

Raster Image Files

FLA file extension

Adobe Flash Animation

Developer Files

VOB file extension

DVD Video Object File

Video Files

INI file extension

Windows Initialization File

Settings Files

FON file extension

Generic Font File

Font Files

7Z file extension

7-Zip Compressed File

Compressed Files

VCXPROJ file extension

Visual C++ Project

Developer Files

BAT file extension

DOS Batch File

Executable Files

ICO file extension

Icon File

System Files

IBOOKS file extension

Multi-Touch iBook

Data Files