In search engine terminology, the results that come up naturally on the search results pages are referred to as organic results. These results show up on Google searches simply because they have been optimized with unique, non-plagiarised content that is rich in keywords.
Certain results come up because website owners pay for them to be there, and these do not count towards organic results. These paid search results and pay per click (PPC) ads are also a huge and integral part of search engine optimization and marketing in their own right.