A method of telling Web browsers and search engines that a Web page or site has been permanently moved to a new location.

A common testing method in which a data source (email address list or Web traffic) is divided into two halves, with one half tested on a variable and the other half serving as the control group.

The HTML tags describing an image that appears when the mouse is rolled over the image on a Web page. Helpful for people who view pages in text-only mode. Some search engines look for keywords in Alt Attributes.

A company that offers Internet access to programs that would otherwise need to be run on a customer’s own server.

A file included in an email message. Attachments need to be encoded and decoded to be emailed.

A method of creating relevant email or Web content based on a user's behavior, including opens and clicks, pages visited or conversions. See also Targeting.

A list of domains or IP addresses that an organization has deemed to be owned by spammers and thus should be blocked.

A limited-scale Web site or page designed for collaborative content generation and frequent updating, also including reader comments on posted material.

A search formed by joining simple terms with AND, OR and NOT for the purpose of limiting or qualifying the search. If you search information on salmon fishing in Alaska, and your search also brings back information on trout fishing and diving in Alaska, the Boolean search "salmon AND fishing AND Alaska NOT diving" can narrow your search focus.

A message that is returned to the server that sent it. A bounced email is usually classified as either a "hard bounce," which indicates a permanent failure due to a non-existent address or a blocking condition by the receiver, or a "soft bounce," indicating that there is a temporary failure due to a full mailbox or an unavailable server. Hard-bouncing message should not be retried. Soft-bouncing messages can be retried one or two times.

Total number of failed (bounced) messages divided by total number of emails sent.

A line of characters in an email message that indicates to the email client that different parts of the message should be "read" differently.

The headline-like text that runs in the bar across the top of the browser window, typically naming and describing the page, often optimized for keyword search or navigation.

Words included in images or text that encourage the prospect to take a specific action. For example, "Click here to see a product tour" or "Add this product to your wish list."

A coordinated set of individual email marketing messages delivered at intervals and with an overall objective in mind. A campaign allows each new message to build on previous success.

Used to identify a site visit referred from a pay-per-click ad, banner ad, paid directory or email campaign, usually used in conjunction with a unique source parameter at the end of the URL that points to a particular landing page or Web site. (e.g. www.example.com/landingpage/?source=googlead)

An extension to HMTL code that allows styles (e.g. color, font, font size) to be specified for certain elements of a hypertext document.

The character set header. Different charsets allow non-western alphabets to be sent via email.

The practice of artificially inflating traffic statistics to defraud advertisers or Web sites that provide venues for advertisers, often by paying users to click links repeatedly or to click on all links regardless of interest or purchase intent.

The percentage of people who click on a link based on the total number who see the link. For example, to calculate the click-through rate of an email campaign, divide the number of unique click-throughs by the number of emails delivered (multiply this number by 100 to express the result as a percentage).

The ratio of unique clicks as a percentage of unique opens. The CTOR measures how effectivly your email message motivated recipients who opened it, to then click a link. In other words, the click-to-open rate expresses the measure of click-through rates as a percentage of messages opened, instead of messages delivered. To calculate the click-to-open rate, divide the number of unique click-throughs by the number of unique emails opened (multiply this number by 100 to express the result as a percentage).

The path a Web site visitor takes throughout the site.  Clickstream analysis shows the site owner how visitors navigate through the site.

User action that requires clicking on a link on a Web page, in an email message, a banner ad, or on a search engine results page to visit an indexed site.  

When a computer interacts with a network (e.g. logging on to the Internet) it becomes the "client" of the "server" computer hosting the files on that network.

The hiding of page content. Involves providing one page for a search engine or directory and a different page for other user agents at the same URL. Legitimate method for stopping page thieves from stealing optimized pages, but frowned upon by some search engines resulting in penalties.