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

WSF file extension

Windows Script File

Executable Files

SITX file extension

StuffIt X Archive

Compressed Files

INDD file extension

Adobe InDesign Document

Layout Files

DESKTHEMEPACK file extension

Windows 8 Desktop Theme Pack File

System Files

SQL file extension

Structured Query Language Data File

Database Files

7Z file extension

7-Zip Compressed File

Compressed Files

TIFF file extension

Tagged Image File Format

Raster Image Files

VCF file extension

vCard File

Data Files

ASX file extension

Microsoft ASF Redirector File

Video Files

BIN file extension

Binary Disc Image

Disk Image Files

IFF file extension

Interchange File Format

Audio Files

MDB file extension

Microsoft Access Database

Database Files

TORRENT file extension

BitTorrent File

Misc Files

APK file extension

Android Package File

Executable Files

XML file extension

XML File

Data Files