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

SRT file extension

SubRip Subtitle File

Video Files

MPG file extension

MPEG Video File

Video Files

EPUB file extension

Open eBook File

eBook Files

JPG file extension

JPEG Image

Raster Image Files

7Z file extension

7-Zip Compressed File

Compressed Files

ZIP file extension

Zipped File

Compressed Files

ROM file extension

N64 Game ROM File

Game Files

WMV file extension

Windows Media Video File

Video Files

VCF file extension

vCard File

Data Files

SWF file extension

Shockwave Flash Movie

Video Files

MAX file extension

3ds Max Scene File

3D Image Files

CBR file extension

Comic Book RAR Archive

Compressed Files

ASPX file extension

Active Server Page Extended File

Web Files

3GP file extension

3GPP Multimedia File

Video Files

HTM file extension

Hypertext Markup Language File

Web Files