The Google +1 button

+1 helps people discover relevant content—a website, a Google search result, or an ad—from the people they already know and trust. The +1 button appears on Google search, on websites, and on ads.

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. 


How it all works!
Now after taking a lot of efforts,you manage to find a article of interest on web.You find it relevant to your area of interest and it seems exactly what you were looking for! You want other users (may be your friends, family members, team mates) to also read the same article when they search for that topic on Google. So now, you can simply

According to Google itself,
"+1 gets conversations going. Click the +1 button to give something your public stamp of approval. Then, if you want to share right away, add a comment and send it to the right circles on Google+.
The next time your friends and contacts search on Google, they could see your +1. You’ll help them find the best stuff on the web – and you might just start up another conversation!"

The idea behind this is very simple. +1 acts as a recommendation from a known source. Recommendation from a known friend, family member or an expert on that particular topic may be of more relevance to you as compared to recommendations from Google crawler.

But this is also been seen as a threat to privacy of users. Of course you can select what pages to +1 on Google, but beware, anything you recommend (even by mistake) may be recorded as a recommended page on your name. This data can also be used as to analyze your browsing habits and interests. Google seems to so desperately get into private life of users.  A article from our blog reviews Facebook and Google's privacy policy and users concerns.