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

ACCDB file extension

Access 2007 Database File

Database Files

PAGES file extension

Pages Document

Text Files

SLN file extension

Visual Studio Solution File

Developer Files

CRDOWNLOAD file extension

Chrome Partially Downloaded File

Misc Files

RA file extension

Real Audio File

Audio Files

HTM file extension

Hypertext Markup Language File

Web Files

SAV file extension

Saved Game

Game Files

PY file extension

Python Script

Developer Files

JSP file extension

Java Server Page

Web Files

7Z file extension

7-Zip Compressed File

Compressed Files

FLA file extension

Adobe Flash Animation

Developer Files

SWF file extension

Shockwave Flash Movie

Video Files

C file extension

C/C++ Source Code File

Developer Files

RPM file extension

Red Hat Package Manager File

Compressed Files

AIF file extension

Audio Interchange File Format

Audio Files