Also called "identity chaos," it is the confusion that arises when users have many unique passwords. With the ever-present warnings not to use the same password for everything, many people do make up a different code for each website. Although Web browsers can save passwords, and sites can store them in the user's computer via cookies, the confusion comes when people access the site from a different machine and have to remember them. To ease the process, a smartphone app can be used (see digital wallet and password manager). One Password Is Not Safe Many people ignore the warnings and use one password acceptable to most sites; for example, at least eight characters, one upper case letter and one digit. However, if their password is ever stolen, it allows the thief access to a great deal of personal information. Combine password chaos with the PIN numbers on credit cards, debit cards and ATM cards, and "welcome to the 21st century." See password, single sign-on, one-time password and two-factor authentication.