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.

While the launch services in OS X use file name extensions to associate files with various applications, generally users do not need to interact with these extensions and the system keeps them hidden ...

File Extension is that which identifies the file type. If you are a regular Windows user, then it is not at all a problem to identify the file type. For it is very important to see file extension to ...