Search engines use complex mathematical algorithms to interpret which websites a user seeks. In this diagram, if each bubble represents a website, programs sometimes called spiders examine which sites link to which other sites, with arrows representing these links. Websites getting more inbound links, or stronger links, are presumed to be more important and what the user is searching for. In this example, since website B is the recipient of numerous inbound links, it ranks more highly in a web search. And the links "carry through", such that website C, even though it only has one inbound link, has an inbound link from a highly popular site (B) while site E does not. Note: Percentages are rounded.
I was used to work with Tools like Sistrix, Ahrefs or Searchmetrics and did not know about SE Ranking before. But those tools were too cost-intensive for a small and quick start into SEO so I tried it out and I am quite satisfied with it. I like the ability to pay for certain services with credits, as I am not using them on a very frequent level, so it actually gives me greater flexibility to only use them when needed and not paying for them even when not using them.
Optimizing a website may involve editing its content, adding content, and modifying HTML and associated coding to both increase its relevance to specific keywords and remove barriers to the indexing activities of search engines like Google ,Yahoo etc. Promoting a site to increase the number of backlinks, or inbound links, is another SEO tactic. By May 2015, mobile search had surpassed desktop search.