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

CFG file extension

Configuration File

Settings Files

DB file extension

Database File

Database Files

FLV file extension

Flash Video File

Video Files

FNT file extension

Windows Font File

Font Files

M4V file extension

iTunes Video File

Video Files

MOV file extension

Apple QuickTime Movie

Video Files

MP4 file extension

MPEG-4 Video File

Video Files

PDB file extension

Program Database

Database Files

PNG file extension

Portable Network Graphic

Raster Image Files

PSPIMAGE file extension

PaintShop Pro Image

Raster Image Files

PY file extension

Python Script

Developer Files

ROM file extension

N64 Game ROM File

Game Files

SRT file extension

SubRip Subtitle File

Video Files

TORRENT file extension

BitTorrent File

Misc Files

TTF file extension

TrueType Font

Font Files