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

INI file extension

Windows Initialization File

Settings Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

MID file extension

MIDI File

Audio Files

VB file extension

VBScript File

Executable Files

DOC file extension

Microsoft Word Document

Text Files

7Z file extension

7-Zip Compressed File

Compressed Files

C file extension

C/C++ Source Code File

Developer Files

NES file extension

Nintendo (NES) ROM File

Game Files

SQL file extension

Structured Query Language Data File

Database Files

DEB file extension

Debian Software Package

Compressed Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

HTM file extension

Hypertext Markup Language File

Web Files

EXE file extension

Windows Executable File

Executable Files

MDB file extension

Microsoft Access Database

Database Files

SRT file extension

SubRip Subtitle File

Video Files