Use the +1 button to publicly show what you like, agree with, or recommend on the web. The +1 button can appear in a variety of places, both on Google and on sites across the web. For example, you might see a +1 button for a Google search result, Google ad, or next to an article you're reading on your favorite news site. Your +1’s and your social connections also help improve the content you see in Google Search. Learn how to +1. Don't have the +1 button yet? Get it now.
What happens when you +1 something?
When you +1 something, the +1 button will turn blue and the +1 will be added to the +1's tab 
of your profile. Here you can manage all your +1’s and decide whether you want to publicly display the +1’s tab.
Regardless of whether you chose to publicly share your +1’s tab, your +1’s will still be visible to others viewing the content you +1’d. For instance, your +1 could appear as part of an anonymous aggregated count of the people who have also +1’d the same thing:
Your name could also appear next to the +1 to help your friends and contacts identify which content may be most useful to them:
When you +1 something, your +1 may be visible to others viewing the content you +1’d.
Control who sees your +1's
You can’t control who sees your +1’s because +1’ing is a public action. Anyone on the Web could potentially see the things you’ve +1’d. Even though your +1’s are public, you can control the privacy of the +1’s tab on your profile.