Facebook is one of the most popular social networking sites over the world, with over 1 billion active users and millions of posts sharing every day. Think about that, if your WordPress site can promote on it with millions of fans, how many visitors can be driven to your site. Luckily, Facebook officially released its Like button that allows users quickly share content on Facebook to freely advertise their companies, products or websites. When readers click the “Like” button on your post, they automatically share your post on their Facebook wall. Facebook advertising requires a lot of trial and error. Every brand, product and company will have a different message and a different audience, and knowing how a given audience will respond is impossible before getting in there and actually trying it.Create ads, create lots of ads and create new ads every day. Even when you find an ad that works, it will have a limited run. I’ve seen ads that perform well for a few days and some that perform well for a few months. The smaller your potential audience, the quicker your ad will fizzle out.There are a lot of different variables that can be tested. Test them all – copy, image, demographics, friend connections, interest groups. They’re all important variables that can dramatically change the results of a given ad. We also protect your privacy by virtue of the way our advertising system works. Because our system chooses which ads to show you, we don’t need to share any of your personal information with advertisers in order to show you relevant ads. In order to advertise on Facebook, advertisers give us an ad they want us to display and tell us the kinds of people they want to reach. We deliver the ad to people who fit those criteria without revealing any personal information to the advertiser. When readers click the “Like” button on your post, they automatically share your post on their Facebook wall. That means your posts or pages can instantly and freely advertise on your readers’ Facebook pages, and attract thousands of their friends at the same times. For instance, a reader with 500 Facebook friends clicks the Like button on your post, so all of the 500 friends will be reminded. Then, they will go to see the updates, and may Like your post as well, and thing continues as this. So, this is the best free word of mouth advertising.