Introducing the World Wide Web

New Features

New HTML codes and client capabilities add a level of robustness to the Web, helping it mature as an information service.

Forms

Before forms were introduced, the Web provided one-way communication. Documents were read, period. Online forms enable two-way communications: document authors can request information for sales, database queries, user feedback, or selective information distribution. For example, a company can now take orders and comments from customers.

Forms have three parts:

HTML offers many online presentation options (e.g., popup and scrolling menus, radio buttons, infinite field length). Forms are not much more difficult to code than other HTML documents.

Because forms collect and process information and generate responses, programs are needed to process this data. Programs can be written in a number of programming languages (e.g., Perl, C++). Programming experience and expertise is required to customize the information processing requirements for a task.

Figure 1.1 Sample form.

Access authentication

Access authentication is a recently-introduced security feature on the Web. Authentication restricts access to a server based on username- or password-level verification, Internet address, or a combination of the two.

It is not apparent that a server is running access authentication until a connection is attempted. A dialog box from the server appears in the client window requesting information (if authentication is based on a username or password). Access to the server contents is permitted or denied depending on the response to the requests for information.

Figure 1.2 Authorization reply from a server.

For the Web to become a base for commercial development, confidentiality and security are paramount. Other security features are available, and more are under development.

Tables

Older Web clients handed tabular information in ASCII format. That is, the tabular information was presented in a fixed-width font with spaces and tabs as needed. This was necessary because HTML and clients had not yet reached the level of sophistication required to handle tables.

Newer versions of Web clients can display formatted tabular information. The HTML coding is more complicated but the results are usually worth the effort. Considerable flexibility (e.g., multiple lines for cells, alignment and border options) has been built-in to HTML table coding so that most information can be accommodated.

Figure 1.3 Sample table.



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