Received a notification from Google about two-step verification? Here’s what it’s all about

Google announced in May that it would start automatically requiring users to adopt two-step verification as a security precaution when they sign into services such as Gmail. That plan, which the company said would expand by the end of this year to 150 million users on mobile and desktop, has now started.

Here’s what you need to know.

What is two-step verification?

Passwords, no matter how strong, may not actually be the best way to keep online accounts secure. Two-step verification, sometimes referred to as two-step authentication, reduces the chances of hackers or other outsiders gaining unauthorized access to your information. This usually means adding an extra security step to log in, like a code sent to your phone via text or a voice call, or a code generated by a Google Authenticator, that users must enter in addition to their usual password.

Why is this happening now?

Google has been encouraging its users to enroll in two-step verification for the past few years. The company has also moved to reduce the need for its users to enter passwords and pushed the use of secure tokens, which instead allow users to sign in to partner websites and apps with a single tap. In addition to the 150 million user accounts Google will automatically enroll in two-step verification this year, creators on sister service YouTube will be required to turn it on by November 1 to access their channels. Google expects that all of its users will eventually be required to login using two-step verification, the company told Fortune.

What’s going to change for me?

You can check whether you’re already enrolled in two-step verification through Google’s Security Checkup. If you’re not, it’s likely you will be eventually. Users who regularly sign in to their account, use Google products on their mobile devices, and who have recovery information on their accounts, like a recovery phone number or email, will be among the first to be automatically enrolled. But if you’re annoyed by the idea of signing in twice, don’t worry. After setting up two-step verification on your computer, you can choose not to use it again on that particular device, and go back to using just your password when you sign in. It’s only when someone else tries to sign in to your account from another computer that users will still have to go through the two-step verification process.

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