I asked question about link building at a forum, someone gave a very detailed answer that I think one should be aware of when building links, the response follows:
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Google has access to all the data they need. They have metrics on the # of scraped links, or link farm links (sabotage?) to expect.
They can simply discount any value of links from specific spam sites, etc.
However, if your site has built up so many links that it surpasses the average threshold by a significant margin, *you* could be *penalized* directly, as it might indicate you are doing some unscrupulous link building strategies.
For example, back in the day you could run a bot that would post a linked message on a million different guestbooks and find yourself at the top of the web search results for hundreds of your top keywords.
Today - that will get likely get your site banned very quickly.
If your site is in every directory out there, has links on many different sites known for link exchanging or link sales, shows up in thousands of blog post comments, etc, then you're definitely asking for trouble.
If you have built links above the threshold (but not spam-level-excessive) from quality sites, to many different pages on your site, using a variety of different anchor text, with a low %-age of links in bad or poor neighborhoods, you should do very well.
--------------------------------------------
Google has access to all the data they need. They have metrics on the # of scraped links, or link farm links (sabotage?) to expect.
They can simply discount any value of links from specific spam sites, etc.
However, if your site has built up so many links that it surpasses the average threshold by a significant margin, *you* could be *penalized* directly, as it might indicate you are doing some unscrupulous link building strategies.
For example, back in the day you could run a bot that would post a linked message on a million different guestbooks and find yourself at the top of the web search results for hundreds of your top keywords.
Today - that will get likely get your site banned very quickly.
If your site is in every directory out there, has links on many different sites known for link exchanging or link sales, shows up in thousands of blog post comments, etc, then you're definitely asking for trouble.
If you have built links above the threshold (but not spam-level-excessive) from quality sites, to many different pages on your site, using a variety of different anchor text, with a low %-age of links in bad or poor neighborhoods, you should do very well.