Google’s 2-Step Verification is an extended security to restrict unauthorized access to your account. 2-Step Verification involves your mobile phone to receive a security code which you need to enter to proceed with logging in. Read more.
Some applications that access your Google Account from your phone, desktop, or other devices (like accessing Gmail(non-web-based) on your Phone or Outlook, desktop Picasa, or even Google Talk) cannot work with 2-Step Verification. To use these applications, you’ll need to enter an application-specific password in the password field instead of your account password.
