Recently I was with a friend and former colleague who keeps getting locked out of his Gmail account. When I asked him if he has two-step verification turned on, he said – no.
Two-step verification is a secondary authentication method when logging onto email, social media, or corporate accounts. Most, if not all, of the major online service providers of email, banking and social media offer two-step verification free of charge. When logging in from an unrecognized computer or mobile device the service provider sends a text message or push notification to an application, like messaging. This ensures no one can access your account even if they have your password.
Check out this link for the instructions on enabling two-step verification on most major sites: http://twofactorauth.org