You can now log into Yahoo Mail without remembering a password

The company introduced a new on-demand login feature that sends users a 

specialized code to their mobile devices to gain access. The code is generated only for that account; since it changes each time you log in, the method is secure. Hackers would have to be in physical possession of a user's smartphone to know the code and thus access the account. Hackers would have to be in physical possession of a user's smartphone to know the code and thus access the account. Many companies like Twitter, Facebook and Google have offered a similar option — two-factor authentication — for some time. This method is like double-locking your door at night (you need both a standard password and the messaged code to enter). Yahoo differs because you don't need a permanent password, just the one that the company sends you on demand. The move, therefore, is technically a form of a one-factor authentication, but it signals a big move by Yahoo to eliminate passwords and also keep the service secure. Last year, the company announced that it was the target of a massive hacking that stole usernames and passwords from its email customers, so the need to provide a safe, encrypted way to keep accounts secure is greater than ever.