The author says that keyword-rich anchor text has long been an SEO best practice. That's because it's a way to signal to search engines about what type of page your link is pointing to. That information is believed by many to play a role when it comes to ranking the page in search results. Anchor text refers to words or phrases that a user clicks on to visit a URL that's linked within a piece of copy. Anchor text is useful for providing context to users on the page they're about to visit, but does it have any impact when it comes to search rankings?
Anchor text is believed to be a ranking factor in the sense that it helps search engines associate URLs with particular keywords or key phrases. The importance of anchor text isn't limited to what search engines can do with it; it's also essential to providing a good user experience through enhancing website accessibility. On-page optimization techniques that improve the user experience tend to correlate positively with search rankings, which is another reason you'll see anchor text listed as a top ranking factor. A good rule of thumb when it comes to optimizing websites is that SEO follows user experience.
When a website is built to provide the best experience for human visitors, it often ends up being optimized for search engines as a result. That's not always true, but you'll come to learn it holds true for anchor text.
Google can get some idea of what the page being linked to (the target page) is about based on words used in anchor text. If a page links to a URL using the anchor text "top 10 pizza places in NYC," then Google knows what type of page users are being directed to visit. With generic text (e.g., "click here"), it's less clear to Google what the target page is about. Just as a site would provide descriptive text to assist users, it should do the same for Google.
Anchor text enhances the user experience in a number of ways. When a user is quickly scanning through an article, descriptive anchor text can help them immediately identify the links they're looking for.
But, with all of that said, it's time to answer the question - is anchor text a ranking factor? Yes, anchor text is a ranking factor. Using descriptive anchor text when inserting links on a page is a best practice listed in Google's SEO Starter Guide.