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

GIF file extension

Graphical Interchange Format File

Raster Image Files

ISO file extension

Disc Image File

Disk Image Files

WPS file extension

Microsoft Works Word Processor Document

Text Files

7Z file extension

7-Zip Compressed File

Compressed Files

SDF file extension

Standard Data File

Data Files

YUV file extension

YUV Encoded Image File

Raster Image Files

ZIP file extension

Zipped File

Compressed Files

WSF file extension

Windows Script File

Executable Files

WAV file extension

WAVE Audio File

Audio Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

MOBI file extension

Mobipocket eBook

eBook Files

VOB file extension

DVD Video Object File

Video Files

BIN file extension

Binary Disc Image

Disk Image Files

C file extension

C/C++ Source Code File

Developer Files

CPL file extension

Windows Control Panel Item

System Files