We always come across sites with category and tag structures that are unmanaged. This issue of excessive use of tags and categories does affect even large news sites. Tags and categories are good examples of the taxonomy system. When a taxonomy system is used in the right way it gives a good impact on your SEO.
Category and Tag Archives
Category and tag archives are essentials for your SEO most importantly for eCommerce sites they are of great help than for individual posts and pages. Archives are landing pages and should be the first results in search engines. They should also offer the best user experience. The more likely your pages are about to expire the more important your categories are. If your site is an online shop and your products change or a job listing site where jobs expire your categories are more important.
Taxonomy SEO prevents your pages from Cannibalism
For example, if you sell Ladie’s bathing suits and you optimize every single page, all the pages will compete against each other for the term ‘ladies bathing suit’. That’s why you should optimize the pages for their specific model, brand and make then create an internal linking pointing the pages to the ‘Ladies bathing suit’ category and now they can rank with more specific terms. That’s how the category page prevents your pages from competing against each other. This works for all types of sites, it also works with blogs if you write blogs about the same topic on a different page, your category for your topic can be one in your search results.