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

GED file extension

GEDCOM Genealogy Data File

Data Files

WPS file extension

Microsoft Works Word Processor Document

Text Files

JAR file extension

Java Archive File

Executable Files

TEX file extension

LaTeX Source Document

Text Files

MPA file extension

MPEG-2 Audio File

Audio Files

TMP file extension

Temporary File

Backup Files

OTF file extension

OpenType Font

Font Files

7Z file extension

7-Zip Compressed File

Compressed Files

VOB file extension

DVD Video Object File

Video Files

M3U file extension

Media Playlist File

Audio Files

JS file extension

JavaScript File

Web Files

COM file extension

DOS Command File

Executable Files

ROM file extension

N64 Game ROM File

Game Files

TOAST file extension

Toast Disc Image

Disk Image Files

THM file extension

Thumbnail Image File

Raster Image Files