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.

Like the GIF (that's Graphics Interchange Format), the PDF (Portable Document Format) has survived and flourished through the digital age. That's partly because of its versatility: It's the go-to ...

A file extension, or file name extension, is the letters immediately shown after the last period in a file name. For example, the file extension.txt has an extension of .txt. This extension allows the ...