Search Engine Eptimization, part 2 - Basics of Links

Hello again! In this second part of my SEO series, I'm going to explain the basics of off-page SEO. As mentioned in my last post, off-page SEO is generally the process of building backlinks to your site and which links are better etc... Here I'll talk about the importance of different links and how to implement this knowledge. I've had to put in this and the previous post, just to set the scene for anyone new to search engine optimization (if you're fairly experienced, skip through for the tips and techniques).
I assume you all know what a backlink is (if not, check out article on backlinks). Many beginners think that to get lots of traffic and a good search engine ranking, you just need to post your link all over the net. This is not the case. Certain backlinks have more 'weight' - influence your ranking better - than others. So what factors determine how much weight a link carries?

The main factor is whether the link is nofollow or dofollow. Nofollow is basically the presence of the 'rel=nofollow' attribute, in the link tag, in the HTML of the page. Dofollow is the absence of this attribute. What a nofollow link does is tells any search engines not to count this link when calculating the website it points to's ranking. Obviously, then nofollow links are not much good unless they are placed in a place on a page that will draw traffic. So you want your links to be dofollow, but many blogs where you can comment or article sites to post articles on use nofollow. Check out this article on dofollow/nofollow links for information on why websites use the nofollow attribute.
Ok then, but how do I tell if a link is nofollow or dofollow? Well, you could sift through tons of HTML markup, but that's not much fun and takes a looonnnggg time. Or you could use a tool like NoDofollow (and add-on for Firefox). What it does is highlights links on a page a different colour depending on whether they are nofollow or dofollow. This way you can see if your favourite article site or blog uses nofollow on their article backlinks or post comments. If the site uses nofollow, I would recommend you put it to the bottom of the of the list of sites you want a backlink on. Don't disregard nofollow links completely - they will still bring valuable traffic if placed in a suitable place on a page, it's just that a dofollow link will do this and help your search engine ranking.
In my next post, I talk about the importance of PageRank (PR) and how to increase your PR, that's where I'll get on to the actual techniques of SEO.
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