They differ in many aspects, from gender to age; from organic to paid; from 1024×768 to 320×480 and onwards. More significantly though, people arrive to your site from across the world: from different countries and languages, different currencies and climates, and a whole assortment of cultural expectations. Hence, even if you have a “.com” English only site, you may very well be an international business by default.
SEO competitive analysis is critical because it gives data about which tactics are working in the industry we are in and what we will need to do to start improving our keyword rankings. The insights gained from this analysis help us understand which tasks we should prioritize and it shapes the way we build out our campaigns. By seeing where our competitors are strongest and weakest, we can determine how difficult it will be to outperform them and the amount of resources that it will take to do so.
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.