SEM can significantly increase a website's visibility on search engine results pages (SERPs). It's a cost-efficient and nonintrusive form of advertising where you only pay when someone clicks on your ad (known as pay-per-click or PPC). This means you can reach your target audience quickly and effectively, without worrying about your marketing budget.   

SEO focuses on improving organic search results for greater search engine ranking, increased website traffic, and increased leads and sales. Integrating SEO tactics into a marketing mix increases the chance of organically ranking higher on SERPs like Google or Bing. The higher on a search engine results page, the more likely people will see it when searching for the products or services they need. As SERP algorithms frequently update and change to help users better find what they need, brands must keep their content, keywords, and rich snippets from pages up to date to improve click-through-rates and organic traffic.