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

FLV file extension

Flash Video File

Video Files

CBR file extension

Comic Book RAR Archive

Compressed Files

SQL file extension

Structured Query Language Data File

Database Files

7Z file extension

7-Zip Compressed File

Compressed Files

MPA file extension

MPEG-2 Audio File

Audio Files

DXF file extension

Drawing Exchange Format File

CAD Files

DTD file extension

Document Type Definition File

Developer Files

XLR file extension

Works Spreadsheet

Spreadsheet Files

GADGET file extension

Windows Gadget

Executable Files

TXT file extension

Plain Text File

Text Files

MSG file extension

Outlook Mail Message

Text Files

MIM file extension

Multi-Purpose Internet Mail Message File

Encoded Files

JPG file extension

JPEG Image

Raster Image Files

VCXPROJ file extension

Visual C++ Project

Developer Files

DOC file extension

Microsoft Word Document

Text Files