Search Engine Marketing (SEM) is marketing in search engines that is primarily text-based, but it can also be ads for products. In Google, you can see it as the top search result with the small “ad” text in front of them and also as the shopping ads. The most common is to use CPC / PPC as a model for payment, but you can also use CPA or CPM. SEM is often one of the most important if not the most important channel for most business models as it meets an explicit need. Paid search is usually divided into generic and branded, where branding is considerably cheaper than generic but something that new companies or small companies can not benefit from the same. There are also different philosophies as to whether one should trust that as “free” SEO should also be able to capture brand search. Or that if someone searches for your brand, they should not be distracted by other brands’ ads (but this is not always the case).