One-pixel links, SEO trick

   This is another deceptive SEO technique. Search engines consider the use of small, almost invisible, graphic image links just one pixel wide and high as an attempt at deception, which may lead to a site ban.

  External factors ranking

    Why inbound links to sites are taken into account
 
As you can see from the previous section, many factors that affect the ranking process are under the control of webmasters. If these were the only factors, then it will be impossible for search engines to distinguish between a genuine high quality document and a page created specifically to achieve high ranking, but contains no information search useful. For this reason, an analysis of inbound links to the site being evaluated, is one of the main factors in page rankings. This is the only factor that is not controlled by the site owner.

   It makes sense to assume that interesting sites will have inbound links. This is because the owners of other sites on the Internet will tend to have published links to a website if they feel it is a valuable resource. Search engine will use this inbound link criterion in its assessment of the significance of the document.

   Therefore, two main factors affect how many pages are stored by search engine and sorted for display in search results:

    - Relevance, as described in the previous section on internal ranking factors.

    - The number and quality of inbound links, also known as Link Popularity Link citation or citation index. This will be described in the next section.

    Link importance (citation index, link popularity)
 
You can easily see that by simply counting the number of inbound links does not give us enough information to assess a country. It is clear that a link from www.microsoft.com means much more than a link from some site www.hostingcompany.com/ myhomepage.html ~. You should take into consideration the importance of the link and the number of connections.

   Search engines use the notion of citation index to assess the number and quality of inbound links to a site. Citation Index is a numerical rating of the popularity of a resource expressed as an absolute value that represents the importance of the page. Each search engine uses its own algorithms to evaluate a citation index page. As a rule, these values ​​are not published.

   As well as the value of absolute citation index, a scaled citation index is sometimes used. This value shows the relative popularity of a site in relation to the popularity of other sites on the Internet. You will find a detailed description of citation indexes and algorithms used for their evaluation in the next sections.