On computers and mobile devices, file extensions are the suffixes that apps append to filenames. When you see an item like "document.docx" for example, the .docx extension tells the computer and the ...

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.

MacOS allows you to hide files and folders by adding a simple period (.) to the file name. This can be handy if you want to share your MacBook with others and hide personal folders that other users ...