File Extension File Type Popularity
EPUB Open EBook Format Very popular ( 5 / 5 )



1. What is the file extension?

The file extension is the string at the end of the full file name. The file extension allows you to identify the type of data contained in a given file. Using the file extension, the operating system associates the file with the appropriate software to handle it.


File name: movie.mkv (MKV file extension, video file)

File name: (ZIP file extension, compressed archive)

File name: configuration.txt (TXT file extension, text file)


2. How do you view file extensions?

Very often the file extensions are hidden in the Windows operating system. To see its extension next to each file, all you have to do is follow these simple steps:

  1. open any folder
  2. click on the VIEW tab
  3. check the "File name extensions" checkbox to show all file extensions.


3. How to open files with unknown file extensions?

There is no definitive answer to this question. Many files that have a text format can be opened with any text editor. Usually, however, for each file extension we need specific software so that the data contained in the file are displayed correctly. Therefore, to properly open a file with an unknown extension, you must find and install the appropriate program to support it.