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

RPM file extension

Red Hat Package Manager File

Compressed Files

CFM file extension

ColdFusion Markup File

Web Files

BIN file extension

Binary Disc Image

Disk Image Files

PPT file extension

PowerPoint Presentation

Data Files

7Z file extension

7-Zip Compressed File

Compressed Files

PNG file extension

Portable Network Graphic

Raster Image Files

SRT file extension

SubRip Subtitle File

Video Files

CSV file extension

Comma Separated Values File

Data Files

XHTML file extension

Extensible Hypertext Markup Language File

Web Files

JSP file extension

Java Server Page

Web Files

PAGES file extension

Pages Document

Text Files

DDS file extension

DirectDraw Surface

Raster Image Files

APK file extension

Android Package File

Executable Files

M3U file extension

Media Playlist File

Audio Files

HTML file extension

Hypertext Markup Language File

Web Files