GuideGoogle and Bing
A ranking is not a visit.
Engine, language, location and device shape search context. Prepare a useful comparison and identify the page worth investigating.
Read the articleGoogle and Bing · Changes in search results
Search results are changing. Know what to check on your site.
Google and Bing updates, new features and official documentation: distinguish an announcement from an available change and identify the queries, pages and markets to check.