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

DBF file extension

Database File

Database Files

DOC file extension

Microsoft Word Document

Text Files

GED file extension

GEDCOM Genealogy Data File

Data Files

GIF file extension

Graphical Interchange Format File

Raster Image Files

M4V file extension

iTunes Video File

Video Files

MP4 file extension

MPEG-4 Video File

Video Files

PRF file extension

Outlook Profile File

Settings Files

PY file extension

Python Script

Developer Files

RTF file extension

Rich Text Format File

Text Files

SAV file extension

Saved Game

Game Files

SRT file extension

SubRip Subtitle File

Video Files

TIF file extension

Tagged Image File

Raster Image Files

TIFF file extension

Tagged Image File Format

Raster Image Files

VCF file extension

vCard File

Data Files

ZIPX file extension

Extended Zip File

Compressed Files