Facebook has launched a new plugin with great appeal to news sites.

“Send” is similar to the “like” function but allows Facebook users (and there are half a billion of them) to send a news story as a private message to an individual, a few friends or a group.

The “send” button can be added to a site’s sharing options, as the Washington Post has done here:

Or users can click the Facebook icon or ‘share’ button and they will then have the option to send the story as a private message.

A Facebook user may come across a gallery of marathon pictures on a news site and decide to “send” the link to everyone who sponsored them. Or a charity may want to “send” a news feature about a campaign to a particular group, which the members can then discuss privately.

According to this Facebook blog post, the ‘send’ button keeps people on your site.

The send button drives traffic by letting users send a link and a short message to the people that would be most interested. They don’t need to leave the web page they’re on or fill out a long, annoying form.

Compared to the alternatives, the send button has fewer required steps, and it removes the need to look up email addresses by auto-suggesting friends and groups.

A small group of news sites and brands launched their ‘send’ buttons yesterday.

Details of how to add the ‘send’ button to your site are at this link.