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

MP3 file extension

MP3 Audio File

Audio Files

DB file extension

Database File

Database Files

GED file extension

GEDCOM Genealogy Data File

Data Files

MOBI file extension

Mobipocket eBook

eBook Files

SAV file extension

Saved Game

Game Files

HQX file extension

BinHex 4.0 Encoded File

Encoded Files

CSR file extension

Certificate Signing Request File

Web Files

PART file extension

Partially Downloaded File

Misc Files

IFF file extension

Interchange File Format

Audio Files

7Z file extension

7-Zip Compressed File

Compressed Files

LUA file extension

Lua Source File

Developer Files

BAT file extension

DOS Batch File

Executable Files

TORRENT file extension

BitTorrent File

Misc Files

MPA file extension

MPEG-2 Audio File

Audio Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files