Google and Links
The Internet landscape is constantly shifting. At one time considered a 'Wild West Frontier' where rules were soft and almost anything went, the net has quickly evolved into a very dense 'megapolis' of countless web properties. Regulations must now be followed in order to maintain a level of harmony and order.
By this analogy, the search engines can be considered the Internet governors who define the rules we live by. But a more suitable parallel would liken the search engines to librarians at a universal library. Imagine if the Dewey Decimal System didn't exist and the librarians didn't care to assist you? With books shelved in a random haphazard fashion, it would be extremely tedious, if not entirely hopeless, to locate specific information. Now imagine such a library with thousands of books added to it each day...good luck finding that book on gardening.
One of the first rules the search engines implemented surrounded meta tags and keywords. In the early days of the net, web site designers had free reign with meta information, and they often tricked the search engines into indexing their sites under irrelevant popular searches by stuffing meta tags with irrelevant content. After a number of years of abuse, the engines began cracking down on this misuse. It was frustrating for users searching for specific information, only to come up empty handed with a surplus of irrelevant results. The engines began to realize that if they wanted to maintain a user base, they needed to correct this issue. The main engines, such as Google, now penalize sites that do not implement appropriate meta information and relevant content. Sites that do not optimize for relevant content are generally ranked poorly within search results or may not be indexed at all. Sites that abuse meta tag rules may be removed entirely from the search engine's index.
With Google, linkage is now succumbing to the same fate. Although links are a very important part of Search Engine Optimization, there are a number of rules of thumb to consider when implementing them.
Keep your links relevant: Google highly values shared relevant links between sites-sites that maintain relevant links are given more weight by Google than sites that share irrelevant links. For example, at one time it was alright for medical sites to share outbound and back links with camera sites. Now, this scenario may have little value. In order to maintain the highest possible benefits, a medical site would do well to only focus on providing links related to its content, such as pharmacy links, or links to other medical sites.
Links also need to be accompanied by at least one paragraph of relevant content. Pages with random nested links and no accompanying relevant content may be penalized.
Link age: In July, 2005, Google changed its algorithms and added an aging factor for back links. The Jagger updates confirm this. Now, the longer a relevant link is active, the more value it has. This means that new links will probably take at least three to four months to be felt. Aged links work best within the body content of a page.
Adding links: Although back links are important, you must use caution when adding them. If too many links are added too quickly, Google may view this as spam, and remove you from its index.
Link placement: Link placement is also important. Links found in the body content of a site have far more value than links located elsewhere. Repeated links throughout a page may also be penalized. Google is trying to simulate human behavior, and feels that human beings would not be apt to click on links from the footer, or be very tolerant of pages that repeat the same links throughout a page.
Link depth: Links should be placed high up in the hierarchy of pages. The higher your links, the more value they have to the search engines. This means back links should be no more than three pages into the site, as a rule of thumb.
Links per page: Sites need at least one inbound link to be listed by Google. Sites without an inbound link might be indexed if they happen to be found by Google's spider, but they will not be listed.
Another good rule of thumb is that a site should not have too many links per page. Too many outbound links may result in the site being penalized and in extreme cases possibly removed from Google's index. Too many reciprocal links per page can make a page look like a 'link farm.'
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