CGI (Common Gateway Interface)
Standard way for a web server to pass a web user's request to an application program and to receive data back to forward to the user. CGI is commonly used to process online forms.

CGI script
CGI scripts are commonly used to handle forms, database search queries on webpages, and to produce dynamic webpage content. The CGI Resource Index is a popular directory containing thousands of CGI / Perl scripts.

Transaction debited to a merchant's account usually as a result of a cardholder dispute.

chat room
Place for web users with a common interest to communicate in real-time.

The process of managing the details between an acquirer and an issuer to allow posting of a cardholder's account and reconciliation of a merchant's settlement position.

click / click through
When a web user clicks on an advertising banner or text ad and lands on the sponsor's webpage. 'Click through' is the more popular term.

click stream
Recorded path of the pages a user visited as they surfed one or more websites.

Program, such as a web browser, that requests the services of another computer. A web browser makes requests for pages from servers all over the Web.

clip art
Prepared artwork designed for use in webpages by experts and novices alike.

clustering / clustered results
Clustering is a technique used by search engines to "cluster" search results together, when they find multiple results from the same website. Usually, the most relevant result is listed first with the other relevant pages from that same site indented below it. This makes search results clearer and more useful to searchers, by preventing a small number of sites occupying all of the top rankings.

When two websites display their logos, and thus their brands, together so that the web user considers the site or section to be a joint venture.

colocation / co-location / collocation
The provision of space for a customer's own computer server in the internet service provider's premises.

comment tag
Comment tags () are used by programmers to add comments to a HTML page and also to hide JavaScript code from non-compliant web browsers.

Content Management System (CMS)
System used to manage the content of a website. Typically, a CMS consists of two elements; the content management application (CMA) and the content delivery application (CDA).

conversion rate
The percentage of people who take a desired action (click, register, subscribe, buy, etc.).

Small information text file that a website stores on your hard disk so that it can remember something about you at a later time. Typically, a cookie records your preferences when using a particular site.

cookie buster
Software that blocks cookies from being placed on a user's browser.

Cost, in terms of a commission payment, to an advertiser for each sale generated by an affiliate.

CPA (Cost-Per-Action)
Cost to an advertiser for each visitor that takes some specifically defined action in response to an ad beyond, such as subscribing to a newsletter.

CPC (Cost-Per-Click)
Cost to an advertiser for each click through of an ad generated by a site visitor.

CPL (Cost-Per-Lead)
Cost to an advertiser for each lead generated by an affiliate.

CPM (Cost-Per-thousand ad impressions)
"M" is taken from the Roman numeral for "thousand."

CPO (Cost-Per-Order)
Cost of advertising based on the number of orders received.

CPT (Cost-Per-Transaction)
Cost of advertising based on the number of transactions received.

crawler / spider / bot
Program that visits and reads webpages in order to create entries for a search engine index.

Banner ads, copy, active URLs and other forms of creative artwork which are due to the ad seller prior to the initiation of an ad campaign.

CRM (Customer Relationship Management)
Management of customer relationships to increasing brand loyalty.

CRON script
A list of one or more commands to a computer operating system or application server that are to be executed (processed) at a specified time.

CSS (Cascading Style Sheets)
CSS defines how to display HTML elements in a webpage.

CTR (Click Through Rate / Ratio)
Percentage of ad impressions that resulted in click throughs.

customer acquisition cost
The cost of acquiring a new customer.

A place, usually a coffee shop, which offers internet access to the public.


Collection of data that is organized so that its contents can be easily accessed, managed, and updated.

Removal of pages from a search engine's index.

Process of interpreting data which is sent in a hard to read form (encrypted).

dedicated server
Rental and exclusive use of a computer that includes a web server, related software, and connection to the internet, housed in the web hosting company's premises.

deep linking
Linking to a page other than the site's home page.

Characteristics of population or audience, such as gender, age group, occupation, income, race, preferences, etc.

description tag
HTML meta tag used to provide a description for search engine listings.