+1 helps people discover relevant content—a website, a Google search result, or an ad—from the people they already know and trust. Adding the +1 button to your pages lets users recommend your content, knowing that their friends and contacts will see their recommendation when it’s most relevant—in the context of Google search results.
When a signed-in Google user is searching, your Google search result snippet may be annotated with the names of the user's connections who've +1'd your page. If none of a user's connections has +1'd your page, your snippet may display the aggregate number of +1's your page has received.
Just copy this code
<!-- Place this tag where you want the +1 button to render -->
<g:plusone></g:plusone>
<!-- Place this tag after the last plusone tag -->
<script type="text/javascript">
(function() {
var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true;
po.src = 'https://apis.google.com/js/plusone.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s);
})();
</script>
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