Search Engine Optimisation
SEO is Search engine optimization, it simply refers to the process of making changes to your website to make it more visible when users search for goods or services associated with your company on Google, Bing, and other search engines. The more visible your pages are in search results, the more likely it is that you will draw attention to your business and draw both new and returning clients.
Your position on the search engine results page depends on a number of factors, one of which is how pertinent your content is to the search query. Since results are only observable over the long term, developing the ideal SEO strategy is truly challenging and is only possible with the help of an expert.
Simply defined, SEO is 100% organic but SEM is a form of marketing where you need pay for your traffic.