What is SEO? Search Engine Optimization (SEO)

Search Engine Optimization (SEO) includes all measures aimed at getting websites to appear in the highest positions on search engine results pages. SEO takes into account how web crawlers from different search engines search, read, and process the contents of web pages, the criteria by which they are evaluated, and how search results are compiled and ranked (search engine ranking). The functioning of the sorting algorithms is kept secret by search engine operators and is often modified to make abuse more difficult and to provide users with truly relevant results. Therefore, it must be deduced indirectly through the analysis of search results. On the contrary, access to and reading of the contents of web pages follow known HTML standards of the web, compliance with which represents the first and fundamental step for optimization. Another step is the choice of appropriate keywords.

Meta tags, which can be inserted in the header of a homepage, are losing importance. Main search engines like Google only rarely take them into account to ensure correct search results.
Important are:

a lot of text with the corresponding presence on the internet, to ensure the highest possible number of keywords.
words that appear in the title of the page (title tag), in highlighted headers (H1, H2 tags, etc.), in text links (including those pointing to the respective page), and within the URL.

Traditional Search Engine Optimization
In traditional search engine optimization, a page is usually optimized for one or two search keywords. Often, an extended page is divided into several individual pages to optimize them for different keywords. In this process, keywords are combined with their related content. This (classic) area falls within the scope of "OnPage optimization"; it indicates all methods and possibilities that can be implemented in the content and structure of a website.
Now, it is no longer sufficient to increase the relevance of web pages alone. Good indexing and good visibility in search engines, as well as the quantity and quality of incoming links to a website (backlinks), must be considered. This area of search engine optimization is called "OffPage optimization".
To assess the potential of a website, free online tools can be used. Often, small changes are sufficient to achieve much better positions in search engines.

Pages designed purely graphically, with embedded videos, images, and graphic texts, as permitted by Flash programming, provide text codes that search engines cannot evaluate. Programming exclusively in Flash is not recommended from a search engine optimization point of view. To still allow the design potential of animated homepages or entire Flash websites without losing ranking, automatic redirects are sometimes created, containing pages of text specifically created for search engines. However, this method of working with so-called "bridge" pages is in conflict with the guidelines of most search engines. The "optimized" landing pages in this way are excluded by search engine operators as soon as they are detected.

Methodologies that lead irrelevant websites to occupy prominent positions in search engine results pages are called search engine spamming; they violate the rules established by search engines to protect the results of their searches from manipulation. Ethically correct search engine optimization avoids spamming. Cases discovered by search engine operators often lead to the exclusion of the respective website.
Ethical search engine optimization (in English white hat search engine optimization) avoids prohibited practices such as the use of bridge pages or a link farm and follows the guidelines of individual search engines. The goal is to avoid punishment by search engines, such as exclusion from the index or downgrading in search engine result pages.