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

AZW file extension

Amazon Kindle eBook File

eBook Files

ASPX file extension

Active Server Page Extended File

Web Files

EPS file extension

Encapsulated PostScript File

Vector Image Files

IBOOKS file extension

Multi-Touch iBook

Data Files

AI file extension

Adobe Illustrator File

Vector Image Files

BAK file extension

Backup File

Backup Files

ASP file extension

Active Server Page

Web Files

COM file extension

DOS Command File

Executable Files

7Z file extension

7-Zip Compressed File

Compressed Files

TMP file extension

Temporary File

Backup Files

TARGZ file extension

Compressed Tarball File

Compressed Files

CUR file extension

Windows Cursor

System Files

DMP file extension

Windows Memory Dump

System Files

DBF file extension

Database File

Database Files

SAV file extension

Saved Game

Game Files