SEO (Search Engine Optimization) Glossary
Pessimization - downgrading website's position in the search engine's output. Normally occurs due to over-optimization of the site - filling it with redundant amount of key phrases - or upon losing a portion of inbound links.
Ban - penalty from a search engine for fraudulent methods of marketing the website (black-hat seo). Such methods include cloaking (when the website is made the way that the search engine "sees" a different text than what is seen by users), invisible text or bought-out inbound links. As a rule, ban is issued for serious violations; because of it, the site can be completely removed from the search engine's output. Returning a once banned website to the search engine's index requires significant efforts.
Trust Rank - degree of confidence search engine puts in the resource. Calculated by complex formulas, considering inbound and outbound links, domain's age, uniqueness of the website domain's IP address, website uptime, and other, often not obvious, parameters.
Supplemental Results. All websites found by the search engine are stored in an internal database (index). There is a huge number of websites all over the world, and not all of their pages are interesting in the context of the search. For such pages, the search engines maintain a separate database. As a rule, the pages that get there have too little of text, contain contact forms, etc. For marketed pages getting in the supplemental results means the "decline of career"; the search engine will show them after all pages from the primary index found by the key phrase.
Snippet - short description of your website generated by the search engine from the website page's head section. A well composed snippet can draw essentially more customers than one sloppily assembled of comma-separated keywords.