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

CAB file extension

Windows Cabinet File

System Files

CFG file extension

Configuration File

Settings Files

DB file extension

Database File

Database Files

DBF file extension

Database File

Database Files

EXE file extension

Windows Executable File

Executable Files

FLA file extension

Adobe Flash Animation

Developer Files

PPT file extension

PowerPoint Presentation

Data Files

RTF file extension

Rich Text Format File

Text Files

SITX file extension

StuffIt X Archive

Compressed Files

SRT file extension

SubRip Subtitle File

Video Files

VCXPROJ file extension

Visual C++ Project

Developer Files

WMA file extension

Windows Media Audio File

Audio Files

XLR file extension

Works Spreadsheet

Spreadsheet Files

ZIP file extension

Zipped File

Compressed Files

ZIPX file extension

Extended Zip File

Compressed Files