"+1 is the digital shorthand for ‘this is pretty cool.'  To recommend something, all you have to do is click +1 on a webpage or ad you find useful. These +1′s will then start appearing in Google's search results,"

The purpose and function of Google's  +1 button is quite similar to Facebook's Like button where users can ‘+1' anything over the internet which will be visible to their circle of friends if they are searching for the same product. This way you can personalize your search results and exchange valuable recommendations from your trusted group of friends.

Apart from search results, users can also find the  +1 button on various websites that Google has partnered with (Mashable, The Huffington Post, TechCrunch, BestBuy are a few to name) so that they can recommend their content of interest.

To start using the  +1 button you first need to have a public Google profile (that will be visible to everyone in your Google address book) so that you and your  user friends can see each others recommended results. In cases where you are looking at a page that has never been "+1″d by your friends, Google will show you an aggregate of +1's it has received from other users.

Users can manage their +1's from a new tab called the profile tab where you can control just how public or private your +1'd items should be.

The +1 button is also available for Ads that appear on the search results pages, so webmasters have a lot to gain as it should increase clicks through to your websites from ads if they've been +1'd by their friends.

Google says:-

"Adding +1 buttons to your pages is a great way to help your content stand out in Google search. By giving your visitors more chances to +1 your pages, your search results and search ads could show up with +1 annotations more often, helping users see when your pages are most likely to be useful."

Though this feature is currently restricted to your Gmail, Buzz, Gtalk, and Google Reader users,  Google hopes to connect it with popular social sites like twitter and Flickr, in the coming days so that the  magic outshines the "Like" craze and Google's another attempt at going social succeeds.