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

ASX file extension

Microsoft ASF Redirector File

Video Files

CLASS file extension

Java Class File

Developer Files

DOC file extension

Microsoft Word Document

Text Files

FNT file extension

Windows Font File

Font Files

GED file extension

GEDCOM Genealogy Data File

Data Files

H file extension

C/C++/Objective-C Header File

Developer Files

JSP file extension

Java Server Page

Web Files

PIF file extension

Program Information File

Executable Files

PL file extension

Perl Script

Developer Files

PS file extension

PostScript File

Vector Image Files

SRT file extension

SubRip Subtitle File

Video Files

SWF file extension

Shockwave Flash Movie

Video Files

VB file extension

VBScript File

Executable Files

VCF file extension

vCard File

Data Files

ZIP file extension

Zipped File

Compressed Files