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

RM file extension

Real Media File

Video Files

7Z file extension

7-Zip Compressed File

Compressed Files

SRT file extension

SubRip Subtitle File

Video Files

M file extension

Objective-C Implementation File

Developer Files

PCT file extension

Picture File

Layout Files

DBF file extension

Database File

Database Files

RA file extension

Real Audio File

Audio Files

CLASS file extension

Java Class File

Developer Files

FNT file extension

Windows Font File

Font Files

TIF file extension

Tagged Image File

Raster Image Files

UUE file extension

Uuencoded File

Encoded Files

CBR file extension

Comic Book RAR Archive

Compressed Files

CUE file extension

Cue Sheet File

Disk Image Files

C file extension

C/C++ Source Code File

Developer Files

PIF file extension

Program Information File

Executable Files