Use Strong, Diverse Passwords

You've heard it a thousand times: Form passwords with combinations of uppercase and lowercase letters, numbers, and symbols. Create unique passwords for each account so that a hacker who nabs your password for a shopping website, for example, can't use it to log in to your e-mail account, too. At least for your most sensitive accounts, such as e-mail and financial portals, change your password regularly. When possible, use two-factor authentication, which involves entering an additional piece of info- say, a code sent to you via text message after an attempt to log in on an unfamiliar device.

To keep track of passwords, you can use an online manager such as Dashlane or LastPass. Such tools are also useful for securely sharing passwords.