Publishers of technology books, eBooks, and videos for creative people

Home > Articles > Web Design & Development > Usability

  • Print
  • + Share This
This chapter is from the book

Dynamic Web Site Basics

In the preceding lessons you explored several concepts that are critical to dynamic site development. One of these is the separation of logic and presentation. The site logic at this point is handled exclusively by XHTML, while the cascading style sheet (CSS) handles the presentation. You have also explored the concept of merging two different documents (an HTML page and a CSS) on the fly to create something different than either of the two source documents alone. These concepts are fundamental to creating dynamic Web sites.

To understand these interactions, and to prepare you for the tasks ahead, let’s take a moment to analyze the relationship among the three different major sources of information that make up every Web page: the content (text, images, etc.); the logic (the document hierarchy, such as headings and body text); and the presentation (the colors, font sizes, positioning, and other cosmetic effects).

In earlier versions of HTML, text, markup, and presentation code all exist in the same place: the HTML document itself. In a meaningful way, the document that a developer creates on her or his hard drive is the same as the document viewed in a browser by the site visitor. This simple relationship is shown in the following figure.

As a result of the upgrades you made in Lesson 2, the relationships have changed: You have separated a document’s presentation from its logic and content. Presentation information is now stored in the CSS. Document content is stored as text within the XHTML markup, which also provides the document logic. Only when the XHTML document and the CSS are merged is the “real” page created. This new relationship is represented in the following figure.

Beginning with this lesson, you are going to add yet another layer of sophistication to this relationship—one that’s more profound and more powerful even than migrating from HTML to XHTML and CSS. Specifically, when you add database content to the site, you will separate the content from the logic. What this means is that all three levels—presentation, logic, and content—are quasi-independent of each other, which means you can make radical changes to one without needing to make changes to another. The relationship—and the basic blueprint for the rest of the book—is shown in the following figure.

HTML cannot separate content from document logic. Even in its fifth major revision as XHTML 1, HTML is ultimately intended to mark up a plain text document. It cannot process scripts, evaluate expressions, do math, interact with a database, or send and receive information to or from a user. Yet separating logic from content requires, at times, each of these abilities and more. To accomplish these tasks, you need to give HTML some help, and this is where server-side technologies such as Microsoft ASP, Macromedia ColdFusion MX, and PHP fit in.

Server technologies like ASP, ColdFusion, and PHP (and there are others, including JSP and ASP.NET) are able to handle programming tasks such as evaluating expressions, doing math, and processing scripts. In addition, they are capable of interacting with data sources, including databases, structured text files, and in some cases XML data. They also have special abilities that pertain only to the Web, such as the ability to collect data sent by the user and control the information that gets sent back to the user.

But there’s a catch. Browsers are limited to handling HTML, CSS, and JavaScript—they don’t understand server scripts (by server scripts, I am referring to code written in ASP, ColdFusion, PHP, and so on). Whatever the server sends to the browser has to be in standard HTML. All server scripts must be processed on the server and output as standard HTML before they get sent to the browser.

To put it more plainly, to view a page with dynamic content, you need to run the page through a server capable of processing the code. This is in contrast to standard HTML pages, which you can view directly in a browser, regardless of whether they go through a server. You can open Internet Explorer or Netscape and browse to any of the HTML pages in the Lesson03/Start folder, and they will display as expected. If you attempt to browse to the pages in the Lesson03/Complete folder, you’ll discover that the pages don’t open (or they open in Dreamweaver, rather than in the browser). The browser sees code it doesn’t understand, and refuses to open the file. This is why, in Lesson 1, you viewed the final version of the site at allectomedia.com, rather than from the CD.

Normally when we think about servers on the Web, we use the term server to refer to the computer that holds the HTML file. This server is properly named the Web server. The most common Web servers include Apache, used on Unix/Linux systems, including Mac OSX; and Microsoft Internet Information Services (IIS), which is used on Windows Web servers.

In addition to the Web server, you will probably use other servers to deliver dynamic data. You may use a database server, such as MySQL or Microsoft SQL Server. You may also use an application server, which processes server scripts. ColdFusion is an application server. The application server that processes ASP scripts is actually built into IIS, so you might say that IIS is a hybrid Web and application server. PHP is an application server that runs as a module inside Apache.

  • + Share This
  • 🔖 Save To Your Account

Peachpit Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Peachpit and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Peachpit products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email ask@peachpit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by Adobe Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.peachpit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020