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

AI file extension

Adobe Illustrator File

Vector Image Files

DNG file extension

Digital Negative Image File

Camera Raw Files

GZ file extension

Gnu Zipped Archive

Compressed Files

MDB file extension

Microsoft Access Database

Database Files

MPA file extension

MPEG-2 Audio File

Audio Files

MPG file extension

MPEG Video File

Video Files

PSPIMAGE file extension

PaintShop Pro Image

Raster Image Files

RA file extension

Real Audio File

Audio Files

RSS file extension

Rich Site Summary

Web Files

TARGZ file extension

Compressed Tarball File

Compressed Files

VCF file extension

vCard File

Data Files

VOB file extension

DVD Video Object File

Video Files

WSF file extension

Windows Script File

Executable Files

XCODEPROJ file extension

Xcode Project

Developer Files

3G2 file extension

3GPP2 Multimedia File

Video Files