One of Microsoft’s attempts at “user friendliness” is that recent versions of Windows are set to hide file extensions. What’s a file extension? As an example, it is the “.exe” that is at the end of a program’s name.

Unfortunately, Microsoft decided that we don’t really need to know what file extensions are. Even worse, they decided that Microsoft programs including Windows might not always consider the file extension, when deciding which program to use with a file.

Huh? That was a lot of words. Let’s take it in shorter sentences.

A file extension is the ending of a file name. For example, Microsoft Word’s file name is WINWORD.EXE. Word, by default, declares to Windows that it owns files with the extension “.doc”. So, if you double-click on a file ending with .doc, Word will try to open it. Similarly, the Notepad program “notepad.exe” declares ownership of the .txt file extension. [By the way, Windows is not case sensitive, so it views Notepad.exe and notepad.EXE and NoTePaD.EXe as the same thing.]

Finally, by default, you do not see file extensions — Windows hides them.

OK, so what’s the problem?

Read more in my article Hidden File Extensions in Windows