what is Google +1 ?

it will help you to get your site listed on the web results based on the keywords that you and your friends used.learn more about google +1 here: http://www.google.com/+1/button/

 

lI think it's like retweet button

 

does it help for seo ?

 

Google +1 button is just like the facebook 'Like' button. It gives opportunity to users with google accounts to recommend something (site or page) to other google users that is in their list of contacts. This button may somehow affect a site's traffic and help a site rank.

 

Source:what-is-google1

 

Google +1 is the equivalent of Facebook likes, it is hoped it will encourage webmasters to build user friendly webpages as opposed to just trying to find a way to beat the search engine algorithms

 

It works in a similar way to the Facebook like button.

 

Absolutely, its now considered an SEO metric.

 

As it's from Google, +1 has been deemed with more authority than the Facebook like button.