Security experts meantime insist there are several forms of encryption, for now, that would be mathematically impractical to break on a large scale. One of them, they say, is PGP (Pretty Good Privacy) encryption, which allows users to encrypt emails on their computer before sending them. (These are different from webmail, where the provider – such as Google, Yahoo, Microsoft – holds the key.) There are still risks of course. In the past, the U.S. government has hacked computers using encrypted technology to view what keys are being hit, former U.S. officials have said.