The HEAD element is contained within the HTML element and includes information about the HTML document.
解答例
The BODY element is contained within the HTML.
The BODY element contains all of the text and other information to be displayed.
Other HTML elements are described in HTML reference manuals.
In traditional media (e.g., television, radio, and newspaper), local advertising is provided by radio stations, television stations, the different newspaper editions, and different newspaper distributors.
The local advertisers target a sub-group, often defined geographically, of the audience for that media outlet.
For example, a local newspaper distributor for a metropolitan city newspaper (e.g., the Houston Chronicle or Los Angeles Times) may include advertising inserts and coupons from local grocers and shopkeepers with the newspaper.
Online advertising on the internet has followed the advertising approach in traditional media.
Advertising space on the internet is sold by web hosts to third parties (advertisers).
Additionally, an advertising agency may be hired by the advertiser to conduct internet advertising.
Advertising space on the internet often appears as a banner or icon on a web page.
Banners often range from 1/2-4 inches high and 4-81/2 inches wide.
The banner or icon may be an image, text, or an image with text.
Additionally, the banner or icon may have a hyperlink to the advertiser's web page.
Thus, if a user clicks on an advertiser's banner, the user's browser will load the advertiser's web page.
Payment schemes for online advertising vary.
For example, an advertiser may pay based on the number of times different users access a web site (referred to as hits or page impressions).
Alternatively, an advertiser may only pay if a user clicks on the advertiser's banner or icon and views the advertiser's web page (referred to as a click-through).
Further, a web host may also receive payment based on any completed transactions that result from a click through (e.g., the web host receives a percentage of the payment received by the advertiser from the user) (referred to as referral commissions).
Advertising schemes attempt to target audiences that would most likely be interested in the product or service being advertised.
For example, the commercials aired in connection with cartoons on television often relate to children's toys, cereal, or other items that children would utilize.
Consequently, the more information known about a viewer or user of a particular web site, the more targeted an advertisement may be.
In existing internet advertising schemes, a web host often provides one advertisement that all clients or users view.
Consequently, there is one global advertisement that all users of the web site see.
Such a global advertisement assumes a homogeneous interest by all users and does not provide different advertisements based on different interests or characteristics of users.
One internet advertising scheme attempts to target specific audiences based on demographics.
For example, a web site that provides information about a specific city (e.g., San Francisco) may attempt to capture local audiences by placing advertisements for businesses located in or near San Francisco.
Thus, advertising on a Yahoo-San Francisco bay web site would attempt to target a local San Francisco bay area audience.
Another advertising scheme bases the advertisement on input from the user.
For example, if a search for baby books were made on a search engine such as Yahoo, the web host for Yahoo may display advertisements relating to baby merchandise such as strollers and high chairs.
