Search engine marketing (SEM) refers to all marketing activities aimed at increasing the visibility of a website or web presence in search engine results. Search engine marketing includes both search engine optimisation (SEO) and search engine advertising (SEA).

Search engine optimisation refers to all measures aimed at increasing the visibility of a website in organic search results. This includes, for example, optimising content, metadata, images and videos as well as improving the loading time and user-friendliness of the website. The aim of SEO is to improve the website's rankings in search engine results and thus drive more traffic to the website.

Search engine advertising, also known as pay-per-click (PPC) advertising, refers to the placement of adverts in search results in return for payment. Advertisers bid on specific keywords and pay for each click on their advert. The adverts usually appear above or below the organic search results and are marked with the word "advert".

The aim of search engine marketing is to increase the visibility of a website in search engine results in order to drive more traffic to the website and ultimately increase the conversion rate. By combining SEO and SEA, companies can strengthen their online presence and achieve their marketing goals more effectively.