A link that points to a page that cannot be found, either because the page no longer exists, the page has moved and a 301 redirect was not put in place, or because the page's web server is down.

The concept in search engine optimization of linking to pages other than the site's homepage (e.g. pages "deep" in the site).

A popular social bookmarking website that allows users to tag, link, and share web pages from a centralized source. Update: now found at Delicious.com

The removal of a website from a search engine's index, whether due to the behavior of those promoting the website or from a bug within the search engine. Also considered a Ban.

The information contained in a META tag and holds a short description of the web page that it is located on. The information in the tag is usually the sentence that is displayed directly after the main link on search engine results pages.

In paid search advertising on Google, the destination URL is actual page users see when they click through an advertiser's ad. This allows the display URL to reference the homepage while the ad directs users to a specific page.

An acronym for Dynamic Hypertext Markup Language. DHTML is a programing language used to create interactive websites. It combines the properties of several other programing languages including HTML, CSS, and JavaScript.

A popular social news website in which users can vote on which stories receive the most exposure. News stories, images, and videos can be submitted by users. There is also a discussion board where users can discuss the latest and most popular submissions.

The process of creating content for the purposes of getting more web traffic from Digg.com.

A website that links to other website via a system of contextual, and generally hierarchical, pages. Listings in directories may be either free or for a fee, and sometimes require a reciprocal link.

In paid search advertising on Google, the display URL is the text located under the body field. It is supposed to represent the URL of the advertisement, but can actually be customized as desired.

A network of websites or search engines and their partner sites on which paid ads can be distributed. The network receives advertisements from the host search engine.

A nickname for the Open Directory Project. DMOZ is short for Directory Mozilla.

A specific website address. For example, the domain name for the Apogee Search website is apogee-search.com. A domain name can be thought of as the location of the Web site on the internet.

Domain Squatting is a process in which users purchase cheap brand- or product-related domains for the purpose of selling at a higher price in the future. Their target tends to be larger businesses who would be willing to spend money on owning their corporate, brand, or product name. This is similar to Twitter Squatting in that there is little risk but the possibility of high profit.