Typically, an attacker will attempt to bypass the username and password system by sending code or characters that confuse the site's programming.

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Financial institutions, one of which was Ford Motor Credit in certain locations, came to realize that someone was apparently using their subscriber code and password to go and access credit reports.

NPR: Understanding Identity Theft

Gmail service offers an option for users to access their email accounts using both a password, and a numerical code separately sent to the authorized user's mobile phone.

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But Passport, which stores personal information on Microsoft's servers, still lets customers use wildly insecure passwords like "password, " and lets anyone who knows your zip code take several cracks at guessing the personal "secret question" that resets the password.

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Entrepreneurs simply choose a username and password, enter an e-mail address and zip code, and sync the site to their QuickBooks software.

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Here, along with your username and password, you can set your Google account to ask you for a six-digit code that Google will send via text message to your phone.

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Two-step verification drastically reduces the chances of someone stealing the personal information from your e-mail account because hackers would have to not only get a password and your user name, they would also have to have access to the mobile phone to which the code is sent.

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