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

WSF file extension

Windows Script File

Executable Files

LOG file extension

Log File

Text Files

SAV file extension

Saved Game

Game Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

PPT file extension

PowerPoint Presentation

Data Files

XLR file extension

Works Spreadsheet

Spreadsheet Files

7Z file extension

7-Zip Compressed File

Compressed Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

GED file extension

GEDCOM Genealogy Data File

Data Files

YUV file extension

YUV Encoded Image File

Raster Image Files

SWF file extension

Shockwave Flash Movie

Video Files

WPD file extension

WordPerfect Document

Text Files

TGA file extension

Targa Graphic

Raster Image Files

MSG file extension

Outlook Mail Message

Text Files

CUR file extension

Windows Cursor

System Files