In recent years, link development has become a major part of search engine marketing and optimiztion. In general, it refers to the practice of obtaining links to one site from other sites.
Links have become increasingly important because search engines use them to rank websites. Google's PageRank scheme is the best known. This system used the linkage of each page to pass PageRank to other pages, both on the same site and different site. Pages with lots of links have more PR, which they can transfer to the pages they link to. Other search engines also use linkage to determine the importance of pages and/or what the page is about.
Hence, improving a site's rankings is often dependent on link development, i.e., convincing other sites to link to the website being promoted. Link development can take many forms, of course, including link hunting, seeking or buying directory listings, buying links, or adding links to sites under the promoter's control. Participating in link farms is another method, but not well-regarded today.
Most link development efforts carefully consider the link anchor text due to its effect on rankings. (The anchor text is a clue to search engines as to what the linked site is about.)
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