The key difference between SEM (Search Engine Marketing) and SEO (Search Engine Optimization) lies in how they help businesses increase their visibility on search engines. SEO focuses on improving a website’s organic ranking by using strategies like keyword optimization, content creation, and link building to rank higher in the search engine results pages (SERPs) naturally, without paying for ads. On the other hand, SEM involves paid advertising strategies, such as Google Ads or Bing Ads, to immediately show up at the top of search results through paid listings. While SEO is a long-term investment in organic growth, SEM offers quicker, immediate results by paying for visibility. Both SEM and SEO can work together to drive traffic, but they serve different purposes in a digital marketing strategy.