Glossary I - O

I

Inbound Link

Link pointing from another website to your own.

You can find out the number of links coming into your website by typing link: infront of your website name in Yahoo! For example try typing link:www.seoukexpert.com into the Yahoo! search box.

Index

Collection of data used as bank to search through to find a match to a user fed query. The larger search engines have billions of documents in their catalogs.
When search engines search they search via reverse indexes by words and return results based on matching relevancy vectors. Stemming and semantic analysis allow search engines to return near matches. Index may also refer to the root of a folder on a web server.

Internal Link

Link from one page on a site to another page on the same site.

Information Architecture

Designing, categorizing, organizing, and structuring content in a useful and meaningful way.
Good information architecture considers both how humans and search spiders access a website. Information architecture suggestions:

focus each page on a specific topic
use descriptive page titles and meta descriptions which describe the content of the page
use clean (few or no variables) descriptive file names and folder names
use headings to help break up text and semantically structure a document
use breadcrumb navigation to show page relationships
use descriptive link anchor text
link to related information from within the content area of your web pages
improve conversion rates by making it easy for people to take desired actions
avoid feeding search engines duplicate or near-duplicate content

Information Retrieval

The field of science based on sorting or searching through large data sets to find relevant information.

Inktomi

Search engine which pioneered the paid inclusion business model. Inktomi was bought by Yahoo! at the end of 2002.

Internet Explorer

Microsoft's web browser. After they beat out Netscape's browser on the marketshare front they failed to innovate on any level for about 5 years, until Firefox forced them to.

Invisible Web

Portions of the web which are not easily accessible to crawlers due to search technology limitations, copyright issues, or information architecture issues.

IP Address

Internet Protocol Address. Every computer connected to the internet has an IP address. Some websites and servers have unique IP addresses, but most web hosts host multiple websites on a single host.
Many SEOs refer to unique C class IP addresses. Every site is hosted on a numerical address like aa.bb.cc.dd. In some cases many sites are hosted on the same IP address. It is believed by many SEOs that if links come from different IP ranges with a different number somewhere in the aa.bb.cc part then the link may count more than links from the same local range and host.

IP delivery (see cloaking)

ISP

Internet Service Providers sell end users access to the web.

Italics

HTML <i> tag gives you italic text </i>

J

JavaScript

A client-side scripting language that can be embedded into HTML documents to add dynamic features.
Search engines do not index most content in JavaScript. In AJAX, JavaScript has been combined with other technologies to make web pages even more interactive.

K

Keyword

A word or phrase which implies a certain mindset or demand that targeted prospects are likely to search for.
Long tail and brand related keywords are typically worth more than shorter and vague keywords because they typically occur later in the buying cycle and are associated with a greater level of implied intent.

Keyword Density

An old measure of search engine relevancy based on how prominent keywords appeared within the content of a page. Keyword density is no longer a valid measure of relevancy over a broad open search index though.
When people use keyword stuffed copy it tends to read mechanically (and thus does not convert well and is not link worthy), plus some pages that are crafted with just the core keyword in mind often lack semantically related words and modifiers from the related vocabulary (and that causes the pages to rank poorly as well).

Keyword Density Analysis Tool

Search Engine Friendly Copywriting - What Does 'Write Naturally' Mean for SEO?
Keyword Funnel
The relationship between various related keywords that searchers search for. Some searches are particularly well aligned with others due to spelling errors, poor search relevancy, and automated or manual query refinement.

Keyword Research

The process of discovering relevant keywords and keyword phrases to focus your SEO and PPC marketing campaigns on.
Example keyword discovery methods:

using keyword research tools
looking at analytics data or your server logs
looking at page copy on competing sites
reading customer feedback
placing a search box on your site and seeing what people are looking for
talking to customers to ask how and why they found and chose your business
Keyword Research Tools
Tools which help you discover potential keywords based on past search volumes, search trends, bid prices, and page content from related websites.
Short list of the most popular keyword research tools:

SEO Book Keyword Research Tool - free, driven by Overture, this tool cross references all of my favorite keyword research tools. In addition to linking to traditional keyword research tools, it also links to tools such as Google Suggest, Buzz related tools, vertical databases, social bookmarking and tagging sites, and latent semantic indexing related tools.
Overture - free, powered from Yahoo! search data. Heavily biased toward over representing commercial queries, combines singular and plural versions of a keyword into a single data point.
Google - free, powered from Google search data.
Wordtracker - paid, powered from Dogpile and MetaCrawler. Due to small sample size their keyword database may be easy to spam.
Please note that most keyword research tools used alone are going to be highly inaccurate at giving exact quantitative search volumes. The tools are better for qualitative measurements. To test the exact volume for a keyword it may make sense to set up a test Google AdWords campaign.

Keyword Stuffing

Writing copy that uses excessive amounts of the core keyword.
When people use keyword stuffed copy it tends to read mechanically (and thus does not convert well and is not link worthy), plus some pages that are crafted with just the core keyword in mind often lack semantically related words and modifiers from the related vocabulary (and that causes the pages to rank poorly as well).

L

Landing Page

The page on which a visitor arrives after clicking on a link, search result or advertisement. You should make your landing pages highly relevant to the advert or search result that the person clicked to enter the website.

 Landing Page Quality Scores

A measure used by Google to help filter noisy ads out of their AdWords program.
When Google AdWords launched affiliates and arbitrage players made up a large portion of their ad market, but as more mainstream companies have spent on search marketing, Google has done many measures to try to keep their ads relevant.

Link (Hyperlink)

A citation from one web document to another web document or another position in the same document.
Most major search engines consider links as a vote of trust.

Link Baiting

The art of targeting, creating, and formatting information that provokes the target audience to point high quality links at your site. Many link baiting techniques are targeted at social media and bloggers.

Link Building

The process of building high quality linkage data that search engines will evaluate to trust your website is authoritative, relevant, and trustworthy.
A few general link building tips:

build conceptually unique linkworthy high quality content
create viral marketing ideas that want to spread and make people talk about you
mix your anchor text
get deep links
try to build at least a few quality links before actively obtaining any low quality links
register your site in relevant high quality directories such as DMOZ, the Yahoo! Directory, and Business.com
when possible try to focus your efforts mainly on getting high quality editorial links
create link bait
try to get bloggers to mention you on their blogs
It takes a while to catch up with the competition, but if you work at it long enough and hard enough eventually you can enjoy a self-reinforcing market position
See also:

101 Ways to Build Link Popularity in 2006 - 101 ways you should and should not build links
Filthy Linking Rich [PDF] - Mike Grehan article about how top rankings are self reinforcing
Link Bursts
A rapid increase in the quantity of links pointing at a website.
When links occur naturally they generally develop over time. In some cases it may make sense that popular viral articles receive many links quickly, but in those cases there are typically other signs of quality as well, such as:

increased usage data
increase in brand related search queries
traffic from the link sources to the site being linked at
many of the new links coming from new pages on trusted domains
See also:

Information retrieval based on historical data

Link Churn

The rate at which a site loses links.

See also:

Information retrieval based on historical data

Link Equity

A measure of how strong a site is based on its inbound link popularity and the authority of the sites providing those links.

Link Farm

Website or group of websites which exercises little to no editorial control when linking to other sites. FFA pages, for example, are link farms.

Log Files

Server files which show you what your leading sources of traffic are and what people are search for to find your website.
Log files do not typically show as much data as analytics programs would, and if they do, it is generally not in a format that is as useful beyond seeing the top few stats.

Link Hoarding

A method of trying to keep all your link popularity by not linking out to other sites, or linking out using JavaScript or through cheesy redirects.
Generally link hoarding is a bad idea for the following reasons:

many authority sites were at one point hub sites that freely linked out to other relevant resources
if you are unwilling to link out to other sites people are going to be less likely to link to your site
outbound links to relevant resources may improve your credibility and boost your overall relevancy scores
"Of course, folks never know when we're going to adjust our scoring. It's pretty easy to spot domains that are hoarding PageRank; that can be just another factor in scoring. If you work really hard to boost your authority-like score while trying to minimize your hub-like score, that sets your site apart from most domains. Just something to bear in mind." - Quote from Google's Matt Cutts

Link Popularity

The number of links pointing at a website.
For competitive search queries link quality counts much more than link quantity. Google typically shows a smaller sample of known linkage data than the other engines do, even though Google still counts many of the links they do not show when you do a link: search.

Link Reputation

The combination of your link equity and anchor text.

Link Rot

A measure of how many and what percent of a website's links are broken.
Links may broken for a number of reason, but four of the most common reasons are:

a website going offline
linking to content which is temporary in nature (due to licensing structures or other reasons)
moving a page's location
changing a domain's content management system
Most large websites have some broken links, but if too many of a site's links are broken it may be an indication of outdated content, and it may provide website users with a poor user experience. Both of which may cause search engines to rank a page as being less relevant.

See also:

Xenu Link Sleuth is a free software program which crawls websites to find broken links.
Live.com
New search platform provided by Microsoft.
See also:

Live.com

Long Tail

Phrase describing how for any category of product being sold there is much more aggregate demand for the non-hits than there is for the hits.
How does the long tail applies to keywords? Long Tail keywords are more precise and specific, thus have a higher value. As of writing this definition in the middle of October 2006 my leading keywords for this month are as follows:

#reqs search term
1504 seo book
512 seobook
501 seo
214 google auctions
116 link bait
95 aaron wall
94 gmail uk
89 search engine optimization
86 trustrank
78 adsense tracker
73 latent semantic indexing
71 seo books
69 john t reed
67 dear sir
67 book.com
64 link harvester
64 google adwords coupon
58 seobook.com
55 adwords coupon
15056 [not listed: 9,584 search terms]

Notice how the nearly 10,000 unlisted terms account for roughly 10 times as much traffic as I got from my core brand related term (and this site only has a couple thousand pages and has a rather strong brand).

See also:

The Long Tail - official blog
The Long Tail - the book

Looksmart

Company originally launched as a directory service which later morphed into a paid search provider and vertical content play.
See also:

Looksmart.com

LSI

Latent Semantic Indexing is a way for search systems to mathematically understanding and representing language based on the similarity of pages and keyword co-occurance. A relevant result may not even have the search term in it. It may be returned based solely on the fact that it contains many similar words to those appearing in relevant pages which contain the search words.
See also:

Quintura Search - free LSI type keyword research tool.
Patterns in Unstructured Data - free paper describing how LSI works
SEO Book articles on LSI: #1 & #2 (Google may not be using LSI, but they are certainly using technologies with similar functions and purpose.)
Johnon Go Words - article about how adding certain relevant words to a page can drastically improve its relevancy for other keywords
M
Malda, Rob
Founder of Slashdot.org, a popular editorially driven technology news forum.
Manual Review
All major search engines combine a manual review process with their automated relevancy algorithms to help catch search spam and train their relevancy algorithms. Abnormal usage data or link growth patterns may also flag sites for manual review.
See also:

Inktomi Spam Database Left Open to Public - article about Inktomi's spam database from 2001
Search Bistro - links to Google's General Guidelines on Random Query Evaluation [PDF] and Google's Spam Guide for Raters
Google Image Labeler - example of how humans can be used to review content
Mechanical Turk
Amazon.com program which allows you to hire humans to perform easy tasks that computers are bad at.
See also:

Mechanical Turk
Google Image Labeler - image labeling game
Human Computation Speech Video at Google
Meme
In The Selfish Gene Richard Dawkins defines a meme as "a unit of cultural transmission, or a unit of imitation." Many people use the word meme to refer to self spreading or viral ideas.
See also:

Techmeme - meme tracker which shows technology ideas that are currently spreading on popular technology blogs
Meta Description
The meta description tag is typically a sentence or two of content which describes the content of the page.
A good meta description tag should:

be relevant and unique to the page;
reinforce the page title; and
focus on including offers and secondary keywords and phrases to help add context to the page title.
Relevant meta description tags may appear in search results as part of the page description below the page title.

The code for a meta description tag looks like this

<meta name="Description" content="Your meta description here. " / >

See also:

Free meta tag generator - offers a free formatting tool and advice on creating meta description tags.
Meta Keywords
The meta keywords tag is a tag which can be used to highlight keywords and keyword phrases which the page is targeting.
The code for a meta keyword tag looks like this

<meta name="Keywords" content="keyword phrase, another keyword, yep another, maybe one more ">

Many people spammed meta keyword tags and searchers typically never see the tag, so most search engines do not place much (if any) weight on it. Many SEO professionals no longer use meta keywords tags.

See also:

Free meta tag generator - offers a free formatting tool and advice on creating meta description tags.
Meta Refresh
A meta tag used to make a browser refresh to another URL location.
A meta refresh looks like this

<meta http-equiv="refresh" content="10;url=http://www.site.com/folder/page.htm">

Generally in most cases it is preferred to use a 301 or 302 redirect over a meta refresh.

Meta Search
A search engine which pulls top ranked results from multiple other search engines and rearranges them into a new result set.
See also:

Myriad Search - an ad free meta search engine
Meta Tags
People generally refer to meta descriptions and meta keywords as meta tags. Some people also group the page title in with these.
The page title is highly important.
The meta description tag is somewhat important.
The meta keywords tag is not that important.
Microsoft
Maker of the popular Windows operating system and Internet Explorer browser.
 
 
 
 
Mindshare
A measure of the amount of people who think of you or your product when thinking of products in your category.
Sites with strong mindshare, top rankings, or a strong memorable brand are far more likely to be linked at than sites which are less memorable and have less search exposure. The link quality of mindshare related links most likely exceeds the quality of the average link on the web. If you sell non-commodities, personal recommendations also typically carry far greater weight than search rankings alone.

See also:

Filthy Linking Rich [PDF] - Mike Grehan article about how top rankings are self reinforcing
Mirror Site
Site which mirrors (or duplicates) the contents of another website.
Generally search engines prefer not to index duplicate content. The one exception to this is that if you are a hosting company it might make sense to offer free hosting or a free mirror site to a popular open source software site to build significant link equity.

Movable Type
For sale blogging software which allows you to host a blog on your website.
Movable Type is typically much harder to install that Wordpress is.

See also:

Movable Type
MSN Search
Search engine built by Microsoft. MSN is the default search provider in Internet Explorer.
See also:

MSN Search
MSN Search Features, Documentation, & Guidelines
Multi Dimensional Scaling
The process of taking shapshots of documents in a database to discover topical clusters through the use of latent semantic indexing. Multi dimensional scaling is more efficient than singular vector decomposition since only a rough approximation of relevance is necessary when combined with other ranking criteria.
MySpace
One of the most popular social networking sites, largely revolving around connecting musicians to fans and having an easy to use blogging platform.
See also:

MySpace.com
N
Natural Language Processing
Algorithms which attempt to understand the true intent of a search query rather than just matching results to keywords.
Natural Link (see Editorial Link)

Natrual Search (see Organic Search Results)

Navigation
Scheme to help website users understand where they are, where they have been, and how that relates to the rest of your website.
It is best to use regular HTML navigation rather than coding your navigation in JavaScript, Flash, or some other type of navigation which search engines may not be able to easily index.

Netscape
Originally a company that created a popular web browser by the same name, Netscape is now a social news site similar to Digg.com.
See also:

Netscape.com
Niche
A topic or subject which a website is focused on.
Search is a broad field, but as you drill down each niche consists of many smaller niches. An example of drilling down to a niche market

search
search marketing, privacy considerations, legal issues, history of, future of, different types of vertical search, etc.
search engine optimization, search engine advertising
link building, keyword research, reputation monitoring and management, viral marketing, SEO copywriting, Google AdWords, information architecture, etc.
Generally it is easier to compete in small, new, or underdeveloped niches than trying to dominate large verticals. As your brand and authority grow you can go after bigger markets.

Nofollow
Attribute used to prevent a link from passing link authority. Commonly used on sites with user generated content, like in blog comments.
The code to use nofollow on a link appears like

<a href="http://wwwseobook.com.com" rel="nofollow">anchor text </a>
Nofollow can also be used in a robots meta tag to prevent a search engine from counting any outbound links on a page. This code would look like this

<META NAME="ROBOTS" CONTENT="INDEX, NOFOLLOW">

Google's Matt Cutts also pushes webmasters to use nofollow on any paid links, but since Google is the world's largest link broker, their advice on how other people should buy or sell links should be taken with a grain of salt. Please note that it is generally not advised to practice link hoarding as that may look quite unnatural. Outbound links may also boost your relevancy scores in some search engines.

O
Ontology
In philosophy it is the study of being. As it relates to search, it is the attempt to create an exhaustive and rigorous conceptual schema about a domain. An ontology is typically a hierarchical data structure containing all the relevant entities and their relationships and rules within that domain.
See also:

Wikipedia: Ontology
Open Directory Project, The (see DMOZ)

Open Source
Software which is distributed with its source code such that developers can modify it as they see fit.
On the web open source is a great strategy for quickly building immense exposure and mindshare.

Opera
A fast standards based web browser.
See also:

Opera.com
Organic Search Results
Most major search engines have results that consist of paid ads and unpaid listings. The unpaid / algorithmic listings are called the organic search results. Organic search results are organized by relevancy, which is largely determined based on linkage data, page content, usage data, and historical domain and trust related data.
Most clicks on search results are on the organic search results. Some studies have shown that 60 to 80% + of clicks are on the organic search results.

Outbound Link
A link from one website pointing at another external website.
Some webmasters believe in link hoarding, but linking out to useful relevant related documents is an easy way to help search engines understand what your website is about. If you reference other resources it also helps you build credibility and leverage the work of others without having to do everything yourself. Some webmasters track where their traffic comes from, so if you link to related websites they may be more likely to link back to your site.

See also:

Live Search: LinkFromDomain:SEOBook.com - shows pages that my site links at.
Overture
The company which pioneered search marketing by selling targeted searches on a pay per click basis. Originally named GoTo, they were eventually bought out by Yahoo! and branded as Yahoo! Search Marketing.
See also:

Yahoo! Search Marketing
Overture Keyword Selector Tool
Popular keyword research tool, based largely on Yahoo! search statistics. Heavily skewed toward commercially oriented searches, also combines singular and plural versions of a keyword into a single version.
See also:

Overture Keyword Selector Tool