SEO Glossary

Backlink

Link from another site on yours.

Black hat

Fraudulent methods to improve the position of a site, such a farm links, satellite page.

Blacklist

A blacklisted site is no longer indexed by search engine.

Cloaking

That consists in presenting to search engines a page different from that which visitors see. That is prohibited and the site may be removed from search engine index. Note that serving HTML to robots while users see Flash or images is viewed as a cloaking trick: the HTML must be viewed by users too.
The JavaScript content and the noscript one must be the same.

Doorway

A doorway page is a page made specifically for search engines, which usually contains significant quantities of links to a site, to emulate a popularity it has not, or internal links to make anchors.That leads to the removal of the site from the index.
An HTML sitemap (with links to the same site) is not considered doorway if its design makes it convenient for visitors.

GWT, Google Webmaster Tools

Panel provided by Google to get statistics and interact with the engine.

HTTP status codes

When a request is made to read a page on a server, an HTTP status code is returned. The main codes are:
- 200: OK, the URL is reached and the page is read.
- 301: redirected permanently. This may be achieved with a PHP function or the .htaccess file.
- 302: redirected temporarily (avoid to use such redirection).
- 404: not found.

Keyword

Keywords are the foundation of SEO, as they are the basis of search engine and source of traffic. They may be choosen for traffic or for money. In the second case they must be relevant with business.
The keyword density is an old measure for SEO.

Meta tag

A meta tag provides informations about a page.

PageRank or ranking

Rank in the Google hierarchy, a score given to a page dependant to backlinks and external links. The more it is raised, the more the page tends to be at the top of the list of answers from search engines (but many other criteria, are taken into account).

ROI (Return On Investsment)

Measurement of how much you earn from each invested dollar.

Sandbox

A site is known sandboxed by Google when its rank page seen to be allowed a rank of 0. It remains indexed, but at the end of the list of results and thus not seen by anyone. This effect can apply to all research that the site answers, or to only a group of keywords in particular.
A new website enters also the sandbox, this is applied by google against spammers that create new sites only to manipulate search engines.

Search Engine

Online tool to find information or a site on the Web (or local engine).

SERP (Search Engine Results Page)

In answer to a search query.

SEO (Search Engine Optimisation)

Techniques to make Web page in such a manner they are best indexed by search engine and get a better position in results.
They consist in architecture of pages, keywords, links and renow.

Sitemap

Map of a site, concretely, a list of URL of the pages which should be indexed, and other information for robots.

Snippet

Name given by Google to the text under the title of a page in results of requests. It may come from the description meta, from Dmoz of from the contents of the page.

Spamming

Processes used to cheat search engines, therefore to privilege its site without regard to the contents, but by making profit of the way robots of search engines work instead. For example, accumulation of keyword, text hidden (white text on white background), pages of links towards its site, etc. This lead to the blacklist.

URL

Uniform Resource Locator, addresses of a site including the domain name and the name of the file, example: http://www.scriptol.com/index.php