5. Ranking system

Ranking is a process whereby the search engine automatically ranks the index data so that, following a query, the most relevant pages appear first in the results list. The aim of ranking is to display the documents that best answer the question in the top 10 results.

To achieve this, search engines are constantly developing new algorithms (mathematical formulas used to classify documents). These algorithms are of course a real differentiating factor between them, and are never published in their entirety. In some cases, they are even protected by hundreds of patents (often analyzed by the English-language site SEO by the Sea) and are sometimes the subject of "defense secrets", or even myths comparable to that of 7X (the main ingredient in Coca-Cola) in the case of the algorithm used by Google.

There are several main methods of ranking results,...