Hard bounce -
Email Message sent to an invalid, closed or nonexistent Email account.

Hashtag -
Use of the hash or pound symbol # used in front of a tag or keyword. Often used on Twitter to help people find discussion on the same topic.

Header -
Routing and program data at the start of an Email message, including the sender’s name and Email address, originating Email server IP address, recipient IP address and any transfers in the process.

Hit -
When users access a Website, their computer sends a request to the site’s server to begin downloading a page. Each element of a requested page (including graphics, text, interactive items) is recorded by the site’s Web server log file as a “hit.” If a page containing two graphics is accessed by a user, those hits will be recorded once for the page itself and once for each of the graphics. Webmasters use hits to measure their servers’ workload. Because page designs and visit patterns vary from site to site, the number of hits bears no relationship to the number of pages downloaded, and is therefore a poor guide for traffic measurement. The proper measures for Website performance include unique users, pageviews, time spent Online, etc.

Home page -
The page designated as the main point of entry of a Website (or main page) or the starting point when a browser first connects to the Internet. Typically, it welcomes you and introduces the purpose of the site, or the organization sponsoring it, and then provides links to other pages within the site.

Host -
Also called server; a computer that provides client stations with access to files and printers as shared resources to a computer network. (See Server).

Hot spot -
A “hot spot” is an area of an ad unit, which when rolled-over/rolled-on by the user’s cursor, such rollover triggers an event (i.e. expand ad). The trigger event should not occur unless the user’s cursor rests in the hotspot zone for at least 1-second. Hotspots should never initiate audio (audio should only be initiated by a click). When hotspots are used, the trigger event should stop immediately upon the user’s cursor leaving the hotspot zone (i.e. ad collapses), and the ad unit should return to its original state.

House list -
The list of Email addresses an organization develops on its own.

HTML message -
Email message which contains any type of formatting other than text. This may be as simple as programming that sets the text in a specific font (bold, italics, Courier 10 point, etc.). It also includes any graphic images, logos and colors.

HTML page -
A HyperText Markup Language document stored in a directory on a Web server and/or created dynamically at the time of the request for the purpose of satisfying that request. In addition to text, an HTML page may include graphics, Video, audio, and other files.

Hybrid pricing -
Pricing model which is based on a combination of a CPM pricing model and a performance-based pricing model. (See CPM, Performance pricing model).

Hyperlink -
HTML programming which redirects the user to a new URL when the individual clicks on hypertext.

Hypertext -
Text displayed on a computer with references hyperlinks to other text that the reader can immediately follow, usually by a mouse click or key-press sequence. This can occur within a document residing on the user’s hard drive or anywhere in the World Wide Web. Apart from running text, hypertext may contain tables, images and other presentational devices. Other means of interaction may also be present, e.g. a bubble with text may appear when the mouse hovers somewhere, a Video clip may be started and stopped, or a form may be filled out and submitted.