I wonder, if Google sees only dofollow sites or links for PR calculation and ignores the nofollow ones, then what would have happened if all the sites in the world were nofollow?

What decides whether a site should be nofollow or dofollow?

If I get a bunch of blogs or forums on searching for some keywords, why is it that some are dofollow and some are not?

What is dofollow?

If all of the sites in the world nofollowed all of their outgoing links, I supposed search engines would be forced to start considering links with nofollow inside the rel attribute as normal links. It's kind of a silly hypothetical question.

To see if a blog is nofollowing their links, look at the page source. If, in the anchor tag, you see this:

<a href="http://external-site.com" rel="nofollow">External Site</a>

then it is a "nofollow link". There is no such thing as "dofollow", that is just a word coined by SEOs to mean "not nofollow". Because it gets used so liberally it causes a lot of confusion.

ya i have seen google count nofollow links in my webmastertools account. but dofollow links may important

Basically, the whole nofollow thing is a result of the sordid history of SERP manipulation.

Back in the '90's search engines used meta keywords. This allowed site owners to add a block saying what the site is all about. All was good.
Then the SERP manipulators came in and started stuffing the keywords with crap. Search result quality suffered.

Then, some folks decided that the number of sites linking in could be a good indicator of a site's relevance, and all was good. Then the SERP manipulators decided to build link farms to mess with the results.

Algorithms changed, and the link farms were given no relevance. Then the SERP manipulators found that they could spam blogs and forums to spread their links.
It first hurt SE users because it became harder to find what they were looking for.
Then it hurt blog and forum owners as the SE's decided to block sites linking to bad neighborhoods; in order to improve the user experience of the SE's users.

To protect the owners of those sites, the kind folks at Google said, just mark your out-going links with rel="nofollow" and we won't count the bad neighborhood against you.

So, now the SERP manipulators are left trying to exploit the last few blogs/forums that haven't made the change or through various link exchange schemes (that are little more than low-density link farming).

Considering that the blog-sphere is dominated by only a handful of blog engines and most forums are run by just a handful of forum engines (all easily identifiable), I expect Google will soon just remove any releavnce to outgoing links from those systems.

Sure they'll traverse and index them, their goal is to index the entire web.

Originally Posted by Cecily

It seems that now Google are not paying as much attention on Dofollow sites as before.

Are you sure about what you're talkin about?! Please think and then post before someone reports you.

Originally Posted by willcode4beer

Basically, the whole nofollow thing is a result of the sordid history of SERP manipulation.

Back in the '90's search engines used meta keywords. This allowed site owners to add a block saying what the site is all about. All was good.
Then the SERP manipulators came in and started stuffing the keywords with crap. Search result quality suffered.

Then, some folks decided that the number of sites linking in could be a good indicator of a site's relevance, and all was good. Then the SERP manipulators decided to build link farms to mess with the results.

Algorithms changed, and the link farms were given no relevance. Then the SERP manipulators found that they could spam blogs and forums to spread their links.
It first hurt SE users because it became harder to find what they were looking for.
Then it hurt blog and forum owners as the SE's decided to block sites linking to bad neighborhoods; in order to improve the user experience of the SE's users.

To protect the owners of those sites, the kind folks at Google said, just mark your out-going links with rel="nofollow" and we won't count the bad neighborhood against you.

So, now the SERP manipulators are left trying to exploit the last few blogs/forums that haven't made the change or through various link exchange schemes (that are little more than low-density link farming).

Considering that the blog-sphere is dominated by only a handful of blog engines and most forums are run by just a handful of forum engines (all easily identifiable), I expect Google will soon just remove any releavnce to outgoing links from those systems.

Sure they'll traverse and index them, their goal is to index the entire web.

Hey mate,,you're SEOGOD! Such a nice post. Thanks a lot. You seem to be knowing the entire history of internet. :-)

I have always thought about what would happen if all sites became nofollow. Personally I think that the big search engines like google would be forced to edit there algorithm to count some nofollow links, but not all of them. Perhaps this would be based on some criteria, such as how its outbound links are organized.

I do predict however them eventually giving some weight to nofollow's

This is my opinion and I COULD be wrong.

Originally Posted by zipity

I do predict however them eventually giving some weight to nofollow's

Why would they?

nofollow was added to protect site owners from comment spam especially from the types of jerks that only post on blogs for a "back link".

People don't add rel="nofollow" to useful links. Most only use it on links from commenting systems (blogs/forums).

Originally Posted by willcode4beer

Then the SERP manipulators came in and started stuffing the keywords with crap. Search result quality suffered.

And now the same people are filling places like Twitter up with the same crap

Originally Posted by blue-dreamer

And now the same people are filling places like Twitter up with the same crap

yea, and those people get the block treatment

I was tiered in searching dofollow blogs....

Originally Posted by Blackjane

I was tiered in searching dofollow blogs....

You can search for "DOFOLLOW BLOG SEARCH ENGINES", but I have seen that so far even the PR4 Search engines are not that effective in fishing out the results with even 10 percent accuracy. So they are as good as useless. I don't care about dofollow or nofollow stuff if the blog or forum is of my niche, but I do care about dofollow when the PR is high and the site is not of my niche. Because even if it doesn't bring me target traffic, it will give me some backlink juice.

Maybe you should be concerned about more useful things than the useless toolbar PR "value" and whether links are nofollow or not.

All sites in the world will be no follow ?
Then they will pay no importance to this tag then

It is NOT a "tag" http://www.webmaster-talk.com/seo-ta...nd-values.html

There will no PR anymore, which is good!...
We'll focus more on increasing our websites traffic and popularity.

Originally Posted by seo-neon

There will no PR anymore, which is good!...
We'll focus more on incresing our websites traffic and popularity.

Some crazy folks already do that, you know.

as one of the posters above said i have also seen many no follow links registered at my google webmaster tool account whereas only a small fraction of my do follow links seem to appear there - articles from searchwarp (no follow links only) are one example that springs to my mind now. i obviously do not know which links are counted and for what. but in theory as PR is becoming less iportant, also due to the consequent use of no follow attibutes, google might asign more value to no follow links and use them for calcualating weights for SERP positions.

Originally Posted by Earnest

Some crazy folks already do that, you know.

Who might that be?...

Originally Posted by seo-neon

Who might that be?...

That would be the people actually trying to build quality content and trying to get people to come back and tell their friends. Content First, SEO always second!