Tutorial: Using Google+ Badges
The badge allows visitors to +1 you, add you to their circles and share content directly from your site without having to leave it!
Google+ pages are a powerful marketing and promotion tool. Before you get started, take a look this Google blog entry, and this article, about how using Google+ Pages can benefit your business profile on the web. You can also take a look at this article about the strategic benefits of using Google+ Pages.
Of course, even if you don't have a Google+ Page, you can add a Google+ badge to your site and encourage visitors to your site to interact with you and share your space.
To get your Google+ badge, visit the Google+ Badge page where you will find steps for creating a personal or business badge.