For most services and accounts, this extra code isn't required every single time you open the app or site—that would get tedious very quickly. Instead, 2FA jumps into action when you try to log in on a new device that you haven't used before or haven't accessed in a long time, like a new phone or a laptop that hasn't been associated with your account in the past.
An authenticator app is one of the best 2FA options, as there's no way for shady characters to intercept the codes without physical access to your phone. (This is a risk with SMS and email.) You have a choice of apps, and the best support the most popular services: Authy is just about the best in the business, while Google and Microsoft offer very competent apps too. Some popular password management apps include an authenticator app, including Dashlane and LastPass.
We're seeing a growing use of biometric information like a fingerprint or a face as that second authentication step, which should make two-factor authentication even more secure and convenient in the future, provided the technology continues to evolve. Adding 2FA is a quick and simple process most of the time, and there's really no excuse not to set it up if you have the option—just remember that it should be used as part of overall good security hygiene, not in isolation.
How to Add Two-Factor Authentication to Your Accounts
Many apps and services offer 2FA now, especially those that store important and sensitive data: emails, financial information, files, social media, contact details, and so on. Most of the accounts that don't have a 2FA option, such as Netflix, for example, aren't at such high risk from attack—hackers usually aren't so interested in binge-watching Netflix Originals and messing with your recommendations.
Every service uses 2FA slightly differently, but the option shouldn't be too hard to find. For Google accounts (which cover Gmail, Google Drive, YouTube, and more), head to your Google account page on the web and then click on Security to find the two-factor option—as the second step of authentication, you can use an authenticator app, have prompts appear on your registered phone, or have SMS codes sent to your cell number.
In the case of Apple accounts, your best option is to use an iPhone or a Mac to switch 2FA on. On iOS, from Settings, tap on your name, then select Password & Security and Turn On Two-Factor Authentication. On macOS, you need to start from System Preferences and then choose Apple ID, Password & Security, and Turn On Two-Factor Authentication. Verification codes can be sent via SMS, and they will appear on other devices using the same Apple ID that you have previously registered with 2FA.