Flash – Flash is a web design technology patented by MacroMedia. Although most search engines are nowadays able to read and index sites developed using the Flash technology they’re still rank quite low and are not recommended by SEO specialists.

Forum – A forum is a certain type of Web 2.0 site that looks like a message board for a virtual community, where users can post different messages or answer to other users’ posts.

Frames – Frames are a web design technology that was quite popular in the early 90s, but which is absolute nowadays. Although most search engines are able to read and index sites using frames they tend to rank low and are not recommended by SEO specialists.

Freshness – The freshness of a web page is determined by the last time when that page was updated. The more frequent a page is updated the more frequent it will be crawled and reindexed by search engine bots, and up to a certain degree the higher it will rank.