This is another program doing much the same as the previous two, but it has a few unique aspects that put it on this list above the hordes of others. Particularly, it comes in many forms; a web interface, a stand-alone browser, a windows or mac executable or even a paid version. In a fit of goodwill, the paid version – costing $30 for the cheapest version – comes with a huge warning to try the free version before buying. It also warns of a lack of refund policy, so buyer beware.
The web is built on links, and web users routinely use links to find the information they need. When a site links to your site, web users follow those links, resulting in web traffic, or referral traffic. When these backlinks, also called inbound links, come from high quality sites, they also tell Google your content is authoritative and trustworthy. This is important because inbound links from respected sites are an SEO ranking factor, so they can boost organic traffic, too.