A message that is displayed on a browser when a file or page is located properly. Although rare, it is possible to see this message even when a file does not exist. The correct response should instead be a 404 error.

A website status code that informs a search engine robot that a page has permanently moved. 301 redirects may be set within certain page types, via a .htaccess file, or even by the web server application itself. A 301 redirect on a page passes along to the new page at least some of the benefits of links to the old page.

A website status code that informs a search engine robot that a page has temporarily moved. 302 redirects may be set via various methods depending upon one's web server platform.

Prevents user access to a particular URL and states the reason why that access has been denied. Usually because the user does not have the authority to view the content. Also known as a "forbidden" message.

A HTTP error returned by a web server to a browser when the requested web page is not available.

A particular approach to designing a website, taking different browsers and search engines into account. This process helps ensure that all users can view the same web content on a website.

A lead or sale generated by a website.

an aggregator, also known as a feed aggregator, feed reader or news reader, is client software or a Web application which collects syndicated web content such as news headlines, blogs, and in one location for easy viewing. An aggregator can be web-based, desktop-based, or on any Internet-connected device.

Shorthand for Asynchronous JavaScript and XML. AJAX is a web development technique that increases usability and speed. It allows specific sections of web page content to update without reloading an entire page. Use of it has led to an increase in interactive animation on web pages.

A service from Amazon.com that ostensibly measures a website's traffic levels. As the only data input for this service is from the tiny percentage of people who have the Alexa toolbar installed, the information is of questionable utility, at best. Good Alexa rankings are inanely easy to fake, but it should be pointed out that you "can't fake bad Alexa rankings".

A specific set of rules or standards that a search engine uses in order to rank listings in response to a query. Search engines typically protect their algorithms since they are unique formulas that are used to determine relevancy in search engine results.

A search engine launched in mid-1999. AllTheWeb gained some prominence by offering a significantly fresher index than its competitors. In February 2003, AllTheWeb was purchased by Overture, and later became part of Yahoo.

A modifier for the IMG tag (which causes images to be shown). It's primary purpose is to provide usability assistance to the visually impaired, but it has real uses in search engine optimization.

An improper term often used to refer to the ALT attribute.

The text placed in an ALT attribute.