| vertical | A vertical or niche is a specific target market or area of operation in internet marketing. |
| 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. |
| clustering | the organising of search results when multiple listings appear for one website. Clustering also refers to the way search engines group different authorities on a certain topic together, showing their relationship. |
| readability | This is the ease with which text on a website may be read and understood. There are some sites where Readability is terrible and there are other sites where its very easy to read and understand what is written. |
| keyword stuffing | A spammy tactic involving the overuse of important keywords and their variants in your content and links. |
