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

ASP file extension

Active Server Page

Web Files

AZW file extension

Amazon Kindle eBook File

eBook Files

BIN file extension

Binary Disc Image

Disk Image Files

DXF file extension

Drawing Exchange Format File

CAD Files

FLV file extension

Flash Video File

Video Files

MIM file extension

Multi-Purpose Internet Mail Message File

Encoded Files

MPG file extension

MPEG Video File

Video Files

PART file extension

Partially Downloaded File

Misc Files

PDB file extension

Program Database

Database Files

PHP file extension

PHP Source Code File

Web Files

SH file extension

Bash Shell Script

Developer Files

TIF file extension

Tagged Image File

Raster Image Files

TTF file extension

TrueType Font

Font Files

XHTML file extension

Extensible Hypertext Markup Language File

Web Files

YUV file extension

YUV Encoded Image File

Raster Image Files