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

CLASS file extension

Java Class File

Developer Files

FLA file extension

Adobe Flash Animation

Developer Files

GED file extension

GEDCOM Genealogy Data File

Data Files

GPX file extension

GPS Exchange File

GIS Files

ISO file extension

Disc Image File

Disk Image Files

JSP file extension

Java Server Page

Web Files

LNK file extension

Windows File Shortcut

System Files

LUA file extension

Lua Source File

Developer Files

PDB file extension

Program Database

Database Files

PHP file extension

PHP Source Code File

Web Files

PRF file extension

Outlook Profile File

Settings Files

RPM file extension

Red Hat Package Manager File

Compressed Files

RTF file extension

Rich Text Format File

Text Files

TGA file extension

Targa Graphic

Raster Image Files

VB file extension

VBScript File

Executable Files