SEO is the work of optimizing a website to meet the requirements of search engines. In simple words, it is a set of methods for promoting site pages in the top 10 search results.
The more pages there are in the top, the more traffic the site will receive. Let's say someone searches the Internet for information on how to choose an interior design style.
The search engine will recognize the query and display relevant pages with articles on this topic. SEO is needed to "show" the search engine that there is information on the page of our site that users need.
Then the search engines will include it in the output. An SEO specialist is working on search engine optimization - a specialist in website promotion in search engines. He collects key queries, analyzes the output, forms recommendations and technical specifications for programmers, designers, copywriters and does a lot more.
SEO is used by online stores, banks, marketplaces, online schools, mass media and many other organizations. For example, you are reading this text, among other things, thanks to SEO.