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

APK file extension

Android Package File

Executable Files

CFM file extension

ColdFusion Markup File

Web Files

CPL file extension

Windows Control Panel Item

System Files

DBF file extension

Database File

Database Files

EPUB file extension

Open eBook File

eBook Files

GED file extension

GEDCOM Genealogy Data File

Data Files

INI file extension

Windows Initialization File

Settings Files

PCT file extension

Picture File

Layout Files

PPT file extension

PowerPoint Presentation

Data Files

SDF file extension

Standard Data File

Data Files

SH file extension

Bash Shell Script

Developer Files

TIF file extension

Tagged Image File

Raster Image Files

VB file extension

VBScript File

Executable Files

XHTML file extension

Extensible Hypertext Markup Language File

Web Files

ZIPX file extension

Extended Zip File

Compressed Files