For example, we regularly create content on the topic of "SEO," but it's still very difficult to rank well on Google for such a popular topic on this acronym alone. We also risk competing with our own content by creating multiple pages that are all targeting the exact same keyword -- and potentially the same search engine results page (SERP). Therefore, we also create content on conducting keyword research, optimizing images for search engines, creating an SEO strategy (which you're reading right now), and other subtopics within SEO.
The leading search engines, such as Google, Bing and Yahoo!, use crawlers to find pages for their algorithmic search results. Pages that are linked from other search engine indexed pages do not need to be submitted because they are found automatically. The Yahoo! Directory and DMOZ, two major directories which closed in 2014 and 2017 respectively, both required manual submission and human editorial review. Google offers Google Search Console, for which an XML Sitemap feed can be created and submitted for free to ensure that all pages are found, especially pages that are not discoverable by automatically following links in addition to their URL submission console. Yahoo! formerly operated a paid submission service that guaranteed crawling for a cost per click; however, this practice was discontinued in 2009.