Microsoft hides file extensions in Windows by default even though it's a security risk that is commonly abused by phishing emails and malware distributors to trick people into opening malicious files.

Every file that we have saved on our computers has a particular extension. The file extension is added at the end of the filename followed by a dot (.). It tells the operating systems about the ...

You're probably aware that most files have an extension such as TXT or EXE after the file name, even though these are not always displayed in Windows. File extensions are how Windows knows what to do ...

In the Mac OS it is possible to change the default program the operating system will use to open a file when you double-click on it. After you have changed this file association, though, you may want ...