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

ACCDB file extension

Access 2007 Database File

Database Files

ASPX file extension

Active Server Page Extended File

Web Files

BAT file extension

DOS Batch File

Executable Files

BIN file extension

Binary Disc Image

Disk Image Files

CRX file extension

Chrome Extension

Plugin Files

CSV file extension

Comma Separated Values File

Data Files

DEB file extension

Debian Software Package

Compressed Files

EXE file extension

Windows Executable File

Executable Files

FLV file extension

Flash Video File

Video Files

PNG file extension

Portable Network Graphic

Raster Image Files

PY file extension

Python Script

Developer Files

RTF file extension

Rich Text Format File

Text Files

SAV file extension

Saved Game

Game Files

TORRENT file extension

BitTorrent File

Misc Files

UUE file extension

Uuencoded File

Encoded Files