| url parameter | The values added to a URL in order to track where traffic comes from (i.e., which link someone clicked on to discover your website or webpage). Here’s an example of a URL parameter (bolded): |
| ahrefs | Founded in 2011 by Dmitry Gerasimenko, Ahrefs is an SaaS SEO platform most popular for its backlink discovery tool Site Explorer. |
| soft 404 | When a non-existent page (a page that has been deleted/removed) displays a ?page not found message or page to anyone trying to access it, but fails to return a HTTP 404 status code. In other words, the content of a web page displayed is entirely unrelated to the HTTP response returned by the server. |
| conceptual links | some of the more advanced search engines are attempting to understand links beyond focusing on the anchor text, for example by using co-citation. |
| gray hat seo | SEO strategies that toe the line of search engine guidelines. They are questionable, but not as clearly in violation of guidelines as black hat SEO tactics. |