There’s obviously a huge number of reasons why a website might link to another and not all of them fit into the categories above. A good rule of thumb on whether a link is valuable is to consider the quality of referral traffic (visitors that might click on the link to visit your website). If the site won’t send any visitors, or the audience is completely unrelated and irrelevant, then it might not really be a link that’s worth pursuing.
Deliver value no matter what: Regardless of who you are and what you're trying to promote, always deliver value, first and foremost. Go out of your way to help others by carefully curating information that will assist them in their journey. The more you focus on delivering value, the quicker you'll reach that proverbial tipping point when it comes to exploding your fans or followers.

Customers are often researching online and then buying in stores and also browsing in stores and then searching for other options online. Online customer research into products is particularly popular for higher-priced items as well as consumable goods like groceries and makeup. Consumers are increasingly using the Internet to look up product information, compare prices, and search for deals and promotions.[21]
Current search engine optimization focuses on techniques such as making sure that each web page has appropriate title tags and that the content is not "thin" or low-quality. High-quality content is original, authoritative, factual, grammatically correct, and engaging to users. Poorly edited articles with spelling and grammatical errors will be demoted by search engines.
There’s a need for a skilled SEO to assess the link structure of a site with an eye to crawling and page rank flow, but I think it’s also important to look at where people are actually surfing. The University of Indiana did a great paper called Ranking Web Sites with Real User Traffic (PDF). If you take the classic Page Rank formula and blend it with real traffic you come out with some interesting ideas……
While ordinary users were not that interested in pages' scores, SEOs of a different caliber felt that this was a great opportunity to make a difference for their customers. This obsession of SEOs with PageRank made everyone feel that this ranking signal is more or less the only important one. In spite of the fact that pages with a lower PR score can beat those with a higher score! What did we receive then, as a result?

Page Rank

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