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

DB file extension

Database File

Database Files

FLV file extension

Flash Video File

Video Files

FNT file extension

Windows Font File

Font Files

GPX file extension

GPS Exchange File

GIS Files

JAR file extension

Java Archive File

Executable Files

MIM file extension

Multi-Purpose Internet Mail Message File

Encoded Files

MP3 file extension

MP3 Audio File

Audio Files

PART file extension

Partially Downloaded File

Misc Files

PHP file extension

PHP Source Code File

Web Files

PPS file extension

PowerPoint Slide Show

Data Files

PS file extension

PostScript File

Vector Image Files

SITX file extension

StuffIt X Archive

Compressed Files

VCF file extension

vCard File

Data Files

XLS file extension

Excel Spreadsheet

Spreadsheet Files

ZIPX file extension

Extended Zip File

Compressed Files