Search engine registration is a request to a search engine to look at a URL and include it into their index. Search engine registration is the quickest method for getting your site listed on public engines. While manual registration is not difficult on most SEs most people use one of the free or for pay registration services/software as a quick way to submit multiple pages to multiple search engines.
An Internal Search Engine allows searching within a site for pages containing certain keywords. Internal SEs are particularly useful on large sites as an alternative to hierarchical menus for site navigation. Many scripts/programs are available to add searching capability to your site.
Search engine indexing describes the process of reading a web page and extracting the content into a database. The term is usually used to describe if a page is in a search engine database, i.e. if a page is indexed. The term "index" is used synonymously with database, i.e. a page is in the search engine index (database).
A spider (also known as a crawler) is a program that browses web sites extracting information for search engine databases. Spiders can be summoned to a site through search engine registration or they will eventually find your site by following links from other sites (assuming you have links from other sites).
Everyone has heard of the prophetic predictions of Nostradamus (e.g., fall of the twin towers), and maybe of even ancients making prophecies as it relates to technology. Although these prophecies are intriguing, a topic more interesting to me is the flipside, technology being able to predict the future.
A Community Portal provides an access gateway to the World Wide Web. Portals bring together local information and offer services like e-mail and discussion forums to extend community activity and interaction. They integrate various information sources and services, such as search engines and directories, and usually enable users to customise the content, layout and navigation to suit their needs. Local needs and interests are central to community portals.
Search engine optimization (SEO) is a set of techniques that tailors your web pages to place well on search engines. Each search engine uses different criteria to determine how to rank web pages. Optimization formats the content of a web page so that it best meets the criteria of what a search engine wants to "see" from a page for top rankings.