Links are vital to increasing traffic online. A website without links isn't going to get any traffic from search, or from other websites. That's the short, nitty-gritty explanation. Now let's take a deeper look.
Links aren't everything in SEO, but search professionals attribute a large portion of the engines'algorithms to link-related factors. Through links, engines can not only analyze the popularity websites and pages based on the number and popularity of pages linking to them, but also metrics like trust, spam, and authority. What's a quality link? It's one of those you'll know it when you see its types of things in many cases. But a link from any large, respectable site is going to be higher on the quality scale than a link you might get from commenting on a blog. In addition, links from those in your neighborhood, sites that are topically relevant to your site, may also count more.
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