Google will take your photo and name that you use in Google Plus—along with any reviews (of songs or movies, for example) that you post to YouTube and Google Play—and put them in ads that your friends and the general public can see.
Google calls these new ads, “shared endorsements”.
Why does Google want to use you in its ads?
Because surveys show that people are more likely to buy a product if that product is recommended by their friends. So, “shared endorsements” means more effective ads, and more effective ads means Google can sell more advertising to businesses.
When Facebook announced in August that it was launching a similar policy privacy groups asked the Federal Trade Commission to examine that plan.
Some people may not mind letting Google use their name, photo and comments “on the more than two million sites in Google's display advertising network, which are viewed by an estimated one billion people” according to the “New York Times”.
Others may want to protect their privacy, or simply object to businesses making money off their name, photo and reviews. If you are one of them, you can choose not to participate in Google's “shared endorsements”.
Choosing not to participate is simple. Just tap or click Google, then sign in with your email and password. Scroll down the page until you see a check box next to text that reads “Based upon my activity, Google may show my name and profile photo in shared endorsements that appear in ads”. Tap or click the check box to clear it and then save.