When would this be useful? If your site has a blog with public commenting turned on, links within those comments could pass your reputation to pages that you may not be comfortable vouching for. Blog comment areas on pages are highly susceptible to comment spam. Nofollowing these user-added links ensures that you're not giving your page's hard-earned reputation to a spammy site.
In Chapter 2, we learned about SERP features. That background is going to help us understand how searchers want to consume information for a particular keyword. The format in which Google chooses to display search results depends on intent, and every query has a unique one. Google describes these intents in their Quality Rater Guidelines as either “know” (find information), “do” (accomplish a goal), “website” (find a specific website), or “visit-in-person” (visit a local business).
Google will select the best title it wants for your search snippet – and it will take that information from multiple sources, NOT just your page title element. A small title is often appended with more information about the domain. Sometimes, if Google is confident in the BRAND name, it will replace it with that (often adding it to the beginning of your title with a colon, or sometimes appending the end of your snippet title with the actual domain address the page belongs to).
QUOTE: “Keyword Stuffed” Main Content Pages may be created to lure search engines and users by repeating keywords over and over again, sometimes in unnatural and unhelpful ways. Such pages are created using words likely to be contained in queries issued by users. Keyword stuffing can range from mildly annoying to users, to complete gibberish. Pages created with the intent of luring search engines and users, rather than providing meaningful MC to help users, should be rated Lowest.” Google Search Quality Evaluator Guidelines 2017
Keywords are as much about your audience as they are about your content, because you might describe what you offer in a slightly different way than some people ask for it. To create content that ranks well organically and drives visitors to your site, you need to understand the needs of those visitors — the language they use and the type of content they seek. You can do this by talking to your customers, frequenting forums and community groups, and doing your own keyword research with a tool like Keyword Explorer.
When using the Keyword Explorer, Ahrefs will also produce the "parent topic" of the keyword you looked up, as you can see in the screenshot above, underneath the Keyword Difficulty meter. A keyword's parent topic is a broader keyword with higher search volume than your intended keyword, but likely has the same audience and ranking potential -- giving you more a valuable SEO opportunity when optimizing a particular blog post or webpage.
Advertising with Google won't have any effect on your site's presence in our search results. Google never accepts money to include or rank sites in our search results, and it costs nothing to appear in our organic search results. Free resources such as Search Console, the official Webmaster Central blog, and our discussion forum can provide you with a great deal of information about how to optimize your site for organic search.