Lately there have been some security issues with Apple accounts. To solve those problems, Apple introduce the two-step authentication for every Apple customer. Now, you can secure your iCloud and Apple ID account using two-step authentication. By enabling this feature, every time you login from a new device to your Apple account you will have to verify your identity. Apple will send a verification code to your mobile device or any other device you listed if you login to your Apple account from a new or unknown location using your Apple ID.To enable this two-step verification feature for your Apple ID, you will need to visit the Apple ID settings page. Log in using your Apple ID and then click on Password and Security from left side navigation menu. You will find the Two-Step Verification option on top of the page with a get started link. Click that link and you will be directed through features and steps of Two-Step Authentication through a couple of pages.Now click continue button and add your existing Apple trusted devices. Then add mobile phone number for the verification process. Now you will get a recovery key which will be the only way to access your account in case you forget your password, so right it down or memorize it. Now your security questions will no longer work, only recovery key will be used to reset password. At final page/step, click on Enable Two-Step Verification button to enable two-step verification for your Apple ID. As for now, this feature is only available for Apple customers from Australia, New Zealand, United States, United Kingdom and Ireland. For a detailed process, click here.
Google accounts also has this two step verification system just like Apple.