Glossary Terms
C

Cache

Copy of a web page stored by a search engine. When you search the web you are not actively searching the
whole web, but are searching files in the search engine index.
Some search engines provide links to cached versions of pages in their search results, and allow you to strip
some of the formatting from cached copies of pages.

Calacanis, Jason

Founder of Weblogs, Inc. Also pushed AOL to turn Netscape into a Digg clone.
See also:

Calacanis.com - Jason's blog

Canonical URL

Many content management systems are configured with errors which cause duplicate or exceptionally similar
content to get indexed under multiple URLs. Many webmasters use inconsistent link structures throughout
their site that cause the exact same content to get indexed under multiple URLs. The canonical version of any
URL is the single most authoritative version indexed by major search engines. Search engines typically use
PageRank or a similar measure to determine which version of a URL is the canonical URL.
Webmasters should use consistent linking structures throughout their sites to ensure that they funnel the
maximum amount of PageRank at the URLs they want indexed. When linking to the root level of a site or a
folder index it is best to end the link location at a / instead of placing the index.html or default.asp filename in
the URL.

Examples of URLs which may contain the same information in spite of being at different web addresses:

http://www.seobusinesssolutions.com/
http://www.seobusinesssolutions/index.html
http://seobusinesssolutions.com/

Catalog (see Index)

Catch All Listing

A listing used by pay per click search engines to monetize long tail terms that are not yet targeted by
marketers. This technique may be valuable if you have very competitive key words, but is not ideal since most
major search engines have editorial guidelines that prevent bulk untargeted advertising, and most of the
places that allow catch all listings have low traffic quality. Catch all listings may be an attractive idea on theme
specific search engines and directories though, as they are already pre qualified clicks.
CGI
Common Gateway Interface - interface software between a web server and other machines or software
running on that server. Many cgi programs are used to add interactivity to a web site.
Client
A program, computer, or process which makes information requests to another computer, process, or
program.
Cloaking
Displaying different content to search engines and searchers. Depending on the intent of the display
discrepancy and the strength of the brand of the person / company cloaking it may be considered reasonable
or it may get a site banned from a search engine.
Cloaking has many legitimate uses which are within search guidelines. For example, changing user
experience based on location is common on many popular websites.

See also:

The Definitive Guide to Cloaking - Dan Kramer's guide to cloaking. I also interviewed Dan here.
KloakIt - cheaply priced cloaking software
Fantomaster - more expensive cloaking software
Cluetrain Manifesto, The
Book about how the web is a marketplace, and how it is different from traditional offline business.
See also:

The Cluetrain Manifesto website - offers the book for free online.

Clustering

In search results the listings from any individual site are typically limited to a certain number and grouped
together to make the search results appear neat and organized and to ensure diversity amongst the top
ranked results. Clustering can also refer to a technique which allows search engines to group hubs and
authorities on a specific topic together to further enhance their value by showing their relationships.
See also

Google Touchgraph - interesting web application that shows the relationship between sites Google returns as
being related to a site you enter.

CMS

Content Management System. Tool used to help make it easy to update and add information to a website.
Blog software programs are some of the most popular content management systems currently used on the
web. Many content management systems have errors associated with them which make it hard for search
engines to index content due to issues such as duplicate content.

Co-citation

In topical authority based search algorithms links which appear near one another on a page may be deemed
to be related to one another. In algorithms like latent semantic indexing words which appear near one another
often are frequently deemed to be related.
Comments
Many blogs and other content management systems allow readers to leave user feedback.
Leaving enlightening and thoughtful comments on someone else's related website is one way to help get
them to notice you.

See also:  blog comment spam - the addition of low value or no value comments to other's websites

Comments Tag

Some web developers also place comments in the source code of their work to help make it easy for people
to understand the code.  HTML comments in the source code of a document appear as <!-- your comment
here -->. They can be viewed if someone types views the source code of a document, but do not appear in
the regular formatted HTML rendered version of a document.

In the past some SEOs would stuff keywords in comment tags to help increase the page keyword density, but
search has evolved beyond that stage, and at this point using comments to stuff keywords into a page adds
to your risk profile and presents little ranking upside potential.

Compacted Information

Information which is generally and widely associated with a product. For example, most published books have
an ISBN.
As the number of product databases online increases and duplicate content filters are forced to get more
aggressive the keys to getting your information indexed are to have a site with enough authority to be
considered the most important document on that topic, or to have enough non compacted information (for
example, user reviews) on your product level pages to make them be seen as unique documents.

Conceptual Links

Links which search engines attempt to understand beyond just the words in them. Some rather advanced
search engines are attempting to find out the concept links versus just matching the words of the text to that
specific word set. Some search algorithms may even look at co-citation and words near the link instead of just
focusing on anchor text.
Concept Search
A search which attempts to conceptually match results with the query, not necessarily with those words, rather
their concept.
For example, if a search engine understands a phrase to be related to another word or phrase it may return
results relevant to that other word or phrase even if the words you searched for are not directly associated
with a result. In addition, some search engines will place various types of vertical search results at the top of
the search results based on implied query related intent or prior search patterns by you or other searchers.

Contextual Advertising


Advertising programs which generate relevant advertisements based on the content of a webpage.
See also:

Google AdSense is the most popular contextual advertising program.
Conversion
Many forms of online advertising are easy to track. A conversion is reached when a desired goal is completed.
Most offline ads have generally been much harder to track than online ads. Some marketers use custom
phone numbers or coupon codes to tie offline activity to online marketing.

Here are a few common example desired goals:  a product sale, completing a lead form, a phone call,
capturing an email, filling out a survey, getting a person to pay attention to you, getting feedback, having a
site visitor share your website with a friend, having a site visitor link at your site, Bid management, affiliate
tracking, and analytics programs make it easy to track conversion sources.

See also:  Google Conversion University - free conversion tracking information, Google Website Optimizer -
free multi variable testing product offered by Google.

Copyright

The legal rights to publish and reproduce a particular piece of work.
See also:

Copyright.gov

Cookie
Small data file written to a user's local machine to track them. Cookies are used to help websites customize
your user experience and help affiliate program managers track conversions.
CPA
Cost per action. The effectiveness of many other forms of online advertising have their effectiveness
measured on a cost per action basis. Many affiliate marketing programs and contextual ads are structured on
a cost per action basis. An action may be anything from an ad click, to filling out a lead form, to buying a
product.
CPC
Cost per click. Many search ads and contextually targeted ads are sold in auctions where the advertiser is
charged a certain price per click.
See also:

Google AdWords - Google's pay per click ad program which allows you to buy search and contextual ads.
Google AdSense - Google's contextual ad program.
Microsoft AdCenter - Microsoft's pay per click ad platform.
Yahoo! Search Marketing - Yahoo!'s pay per click ad platform
CPM
Cost per thousand ad impressions.
Many people use CPM as a measure of how profitable a website is or has the potential of becoming.

Crawl Depth


How deeply a website is crawled and indexed.
Since searches which are longer in nature tend to be more targeted in nature it is important to try to get most
or all of a site indexed such that the deeper pages have the ability to rank for relevant long tail keywords. A
large site needs adequate link equity to get deeply indexed. Another thing which may prevent a site from
being fully indexed is duplicate content issues.

Crawl Frequency
How frequently a website is crawled.
Sites which are well trusted or frequently updated may be crawled more frequently than sites with low trust
scores and limited link authority. Sites with highly artificial link authority scores (ie: mostly low quality spammy
links) or sites which are heavy in duplicate content or near duplicate content (such as affiliate feed sites) may
be crawled less frequently than sites with unique content which are well integrated into the web.

See also:  Google's Matt Cutts video on Google Crawling Patterns
Matt Cutts post Indexing Timeline - mentions sites with unnatural link profiles may not be crawled as
frequently or deeply

CSS
Cascading Style Sheets is a method for adding styles to web documents.
Note: Using external CSS files makes it easy to change the design of many pages by editing a single file. You
can link to an external CSS file using code similar to the following in the head of your HTML documents

<link rel="stylesheet" href="http://www.seobook.com/style.css" type="text/css" />

See also:  W3C: CSS - official guidelines for CSS, CSS Zen Garden - examples of various CSS layouts
Glish.com - examples of various CSS layouts, links to other CSS resources

CTR
Clickthrough rate - the percentage of people who view click on an advertisement they viewed, which is a way
to measure how relevant a traffic source or keyword is. Search ads typically have a higher clickthrough rate
than traditional banner ads due to being highly relevant to implied searcher demand.
Cutts, Matt
Google's head of search quality.
See also:  Matt Cutts blog, Interview of Matt Cutts
SEO Videos by Matt Cutts

Cybersquatting
Registering domains related to other trademarks or brands in an attempt to cash in on the value created by
said trademark or brand.

                                                                       
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