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

PAGES file extension

Pages Document

Text Files

CBR file extension

Comic Book RAR Archive

Compressed Files

7Z file extension

7-Zip Compressed File

Compressed Files

BAT file extension

DOS Batch File

Executable Files

PPT file extension

PowerPoint Presentation

Data Files

RA file extension

Real Audio File

Audio Files

M4V file extension

iTunes Video File

Video Files

XLSX file extension

Microsoft Excel Open XML Spreadsheet

Spreadsheet Files

ZIP file extension

Zipped File

Compressed Files

AIF file extension

Audio Interchange File Format

Audio Files

IFF file extension

Interchange File Format

Audio Files

AZW file extension

Amazon Kindle eBook File

eBook Files

THM file extension

Thumbnail Image File

Raster Image Files

DEM file extension

Video Game Demo File

Game Files

RPM file extension

Red Hat Package Manager File

Compressed Files