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

BMP file extension

Bitmap Image File

Raster Image Files

CBR file extension

Comic Book RAR Archive

Compressed Files

CFM file extension

ColdFusion Markup File

Web Files

DBF file extension

Database File

Database Files

DWG file extension

AutoCAD Drawing Database File

CAD Files

GPX file extension

GPS Exchange File

GIS Files

HQX file extension

BinHex 4.0 Encoded File

Encoded Files

LOG file extension

Log File

Text Files

OBJ file extension

Wavefront 3D Object File

3D Image Files

PART file extension

Partially Downloaded File

Misc Files

PDB file extension

Program Database

Database Files

PNG file extension

Portable Network Graphic

Raster Image Files

SH file extension

Bash Shell Script

Developer Files

SLN file extension

Visual Studio Solution File

Developer Files

TGA file extension

Targa Graphic

Raster Image Files