s who seek an even higher level of security protection, including s whose s could be attractive targets for hackers, such as celebrities, politicians, journalists, political activists and wealthy individuals, can opt-in to Google's Advanced Protection Program. This program requires the to purchase two U2F USB keys — not for data storage, but for identity verification. The U2F keys are used to provide two-step verification during . One is for backup purposes, in case the first is lost. The Advanced Protection Program includes further security measures to protect the 's , such as restrictions on which applications the can grant access to their , and a more thorough identity verification process for regaining access to the if the is forgotten.[11] On June 5, 2012, a new security feature was introduced to protect s from state-sponsored attacks. Whenever Google analysis indicate that a government has attempted to comp