You can confer some of your site's reputation to another site when your site links to it. Sometimes users can take advantage of this by adding links to their own site in your comment sections or message boards. Or sometimes you might mention a site in a negative way and don't want to confer any of your reputation upon it. For example, imagine that you're writing a blog post on the topic of comment spamming and you want to call out a site that recently comment spammed your blog. You want to warn others of the site, so you include the link to it in your content; however, you certainly don't want to give the site some of your reputation from your link. This would be a good time to use nofollow.
Disclaimer: Even when I joined the company in 2000, Google was doing more sophisticated link computation than you would observe from the classic PageRank papers. If you believe that Google stopped innovating in link analysis, that’s a flawed assumption. Although we still refer to it as PageRank, Google’s ability to compute reputation based on links has advanced considerably over the years. I’ll do the rest of my blog post in the framework of “classic PageRank” but bear in mind that it’s not a perfect analogy.
These are ‘tit-for-tat’ links. For instance, you make a deal with your friend who has a business website to have him place a link to your website, and in exchange your website links back to his. In the dark ages of SEO, this used to be somewhat effective. But these days, Google considers such 'link exchanges' to be link schemes, and you may get hit with a penalty if you're excessive and obvious about it. This isn't to say that swapping links is always bad, but if your only motive is SEO, then odds are that you shouldn't do it.

Keyword analysis. From nomination, further identify a targeted list of key­words and phrases. Review competitive lists and other pertinent industry sources. Use your preliminary list to determine an indicative number of recent search engine queries and how many websites are competing for each key­word. Prioritize keywords and phrases, plurals, singulars and misspellings. (If search users commonly misspell a keyword, you should identify and use it). Please note that Google will try to correct the term when searching, so use this with care.

Suggesting that this change is really just the equivalent of “resetting” things to the way they were is absurd. nofollow is still be using on outbound links in mass by the most authoritative/trusted sites on the web. Allowing us peons to have a slight bit of control over our internal juice flow simply allowed us to recoup a small portion of the overall juice that we lost when the top-down flow was so dramatically disrupted.
This year, for the first time, Google stated that user experience would be a core part of gaining rankings for mobile websites. A poorer user experience would send your site hurtling down the rankings. This appeared to come as a shock to many in the SEO community and despite assurances that content was still king – many seemed to feel that this ...
Understand that whatever you're going to do, you'll need traffic. If you don't have any money at the outset, your hands will be tied no matter what anyone tells you. The truth is that you need to drive traffic to your offers if you want them to convert. These are what we call landing pages or squeeze pages. This is where you're coming into contact with the customers, either for the first time or after they get to know you a little bit better.
Suppose instead that page B had a link to pages C and A, page C had a link to page A, and page D had links to all three pages. Thus, upon the first iteration, page B would transfer half of its existing value, or 0.125, to page A and the other half, or 0.125, to page C. Page C would transfer all of its existing value, 0.25, to the only page it links to, A. Since D had three outbound links, it would transfer one third of its existing value, or approximately 0.083, to A. At the completion of this iteration, page A will have a PageRank of approximately 0.458.
The total number of backlinks can often include many links from the same referring domain or multiple referring domains. It’s common for referring domains to link back to your content if it is relevant, authoritative or useful in some way to their own domain. In an ideal world, that’s how backlinks are accumulated; unique content that other websites want to be associated with.

My final (thank goodness) point on this is not that (white hat) PageRank sculpitng was really anything special. It was just quite logical. It really feels like we are going down a wrong route here. Shall we outlaw cars because some people drive dangerously? Or should we do all we can to make driving safer? Not on the same level in any way, but you can see my point here. This is the first time I have felt that you have made a bad call and that is the only reason I am making a case for the logics of this.

I segmented different verticals, did a Google search to see which website ranked #1 for that query (keep in mind that I performed this search using a VPN and not at the targeted location to get 'cleaner' results, so yours would be different, especially for local types of businesses), added it to my list, and then averaged out the percentages of link types (which I pulled from Click the link below to see my dataset.
I would like to know how Google is handling relevancy with so many websites now jumping on the “no follow” wagon? Seems like just about every major website has no follow links, so with the Panda updates this year what’s happening to all that lost link power? Seem’s like this tactic will stagnate the growth of up-and-coming websites on the internet to me. Am I right here?
Matt Cutts, it’s Shawn Hill from Longview, Texas and I’ve got to say, “you’re a semseo guru”. That’s obviously why Google retained you as they did. Very informative post! As head of Google’s Webspam team how to you intend to combat Social Networking Spam (SNS)? It’s becoming an increasingly obvious problem in SERPs. I’m thinking Blogspam should be the least of Google’s worries. What’s your take?

Gotta love Google. They turn the entire SEO/webmaster world on its head with an announcement of a new attribute in 2005. We all go out and make changes to our sites to take advantage of this new algorithm change that is said to benefit out sites. And then 2 years later, they change their mind and rewrite the code – and dont bother to tell anyone. And then a YEAR LATER, they make an announcement about it and defend the change by saying “the change has been in effect for over a year, so if you haven’t noticed obviously it isnt that big a deal”
I work on a site that allows users to find what they are looking for by clicking links that take them deeper and deeper into the site hierarchy. Content can be categorised in lots of different ways. After about three steps the difference between the results pages shown is of significance to a user but not to a search engine. I was about to add nofollow to links that took the browser deeper than 3 levels but after this announcement I won’t be…
I think that removing the link to the sitemap shouldn’t be a big problem for the navigation, but I wonder what happens with the disclaimer and the contact page? If nofollow doesn’t sink the linked page, how can we tell the search engine that these are not content pages. For some websites these are some of the most linked pages. And yes for some the contact page is worth gaining rank, but for my website is not.