You will find a lot of websites or program in the market, which claims to increase website traffic and promote social network. But, not all the programs are good enough to provide you effective and free traffic on your website. However, the following is the list of websites, which provides effective and relevant visitors on your website, and that too free of cost:

1. Twitter: No doubt, one of the best social media marketing websites which ensures that your message reached millions of users, in no time. All you have to do is to get followers for your twitter account.

2. Facebook: Facebook has travelled a long way from being a social networking website to a social media marketing website. With over 700 million members, you cn't deny the fact that it has the power to bring humongous traffic on your website.

3. Traffup.net : Traffup is the number one tool to bring effective and free traffic on your websites, and to bring free twitter followers on your twitter account, instantly. The best thing about traffup is that it brings effective and relevant visitors and followers on your website and twitter account, respectively. And that too, free of cost. This helps you to grow social network to a great extent.

4. Hubpages: You can promote your website by writing articles or hubs about it on Hubpages. You can attract a lot of people through this website. But do make sure to share some useful information with the users in order to ensure more readers for your hubs, and more traffic on your website.

5. Squidoo: The best thing about squidoo is that you can promote your website's article and your website feeds, simultaneously in order to bring free traffic on it.

6. Digg: Digg is the number one social bookmarking website which helps to promote your website free of cost by submitting URL of your website with proper title and description, in order to bring free and effective visitors on your website.

7. Reddit: Much on the lines of digg, you have reddit. reddit helps you to promote your website by sharing URL of your website. Reddit helps in preventing spam websites, thanks to its strict rules.

9. Ycombinator: Y combinator is an emerging social bookmarking website, which has brough a lot of traffic to my website "Management Point". Though, you can't expect continuous traffic on your website through it, but it is still a great way to bring free traffic on your websites.

10. Online forums like digital point etc: The most important way of promoting your website is by sharing useful information about your website in online forums like digital point, w junction etc. You can easily find the list oof online forums related to your website, where you can promote your website.