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

PPTX file extension

PowerPoint Open XML Presentation

Data Files

MDB file extension

Microsoft Access Database

Database Files

WMA file extension

Windows Media Audio File

Audio Files

7Z file extension

7-Zip Compressed File

Compressed Files

CRDOWNLOAD file extension

Chrome Partially Downloaded File

Misc Files

FLA file extension

Adobe Flash Animation

Developer Files

PDF file extension

Portable Document Format File

Layout Files

DOCX file extension

Microsoft Word Open XML Document

Text Files

YUV file extension

YUV Encoded Image File

Raster Image Files

PL file extension

Perl Script

Developer Files

AIF file extension

Audio Interchange File Format

Audio Files

ROM file extension

N64 Game ROM File

Game Files

DLL file extension

Dynamic Link Library

System Files

MIM file extension

Multi-Purpose Internet Mail Message File

Encoded Files

MAX file extension

3ds Max Scene File

3D Image Files