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

DAT file extension

Data File

Data Files

TARGZ file extension

Compressed Tarball File

Compressed Files

JPG file extension

JPEG Image

Raster Image Files

JS file extension

JavaScript File

Web Files

7Z file extension

7-Zip Compressed File

Compressed Files

EPS file extension

Encapsulated PostScript File

Vector Image Files

DTD file extension

Document Type Definition File

Developer Files

PS file extension

PostScript File

Vector Image Files

KMZ file extension

Google Earth Placemark File

GIS Files

PDF file extension

Portable Document Format File

Layout Files

DB file extension

Database File

Database Files

RAR file extension

WinRAR Compressed Archive

Compressed Files

PDB file extension

Program Database

Database Files

DNG file extension

Digital Negative Image File

Camera Raw Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files