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Understanding HTML and XHTML Connections

Learn the various elements that must appear in an HTML file, including how to include all the HTML Tags that every web page must have, how to organize a page with paragraphs, line breaks and headings, how to validate your web content, and how to differentiate between HTML, XML, XHTML, and HTML 5.
This chapter is from the book


  • How to create a simple web page in HTML
  • How to include all the HTML Tags that every web page must have
  • How to organize a page with paragraphs and line breaks
  • How to organize your content with headings
  • How to validate your web content
  • How to differentiate between HTML, XML, XHTML, and HTML 5

The first two hours gave you a basic idea of the process behind creating web content and viewing it online or locally, if you do not yet have a web hosting provider. In this hour, we'll get down to the business of explaining the various elements that must appear in an HTML file.

At the end of the hour, you'll learn how HTML differs from XHTML and why there are two different languages designed to do the same thing—create web content. In general, this hour provides a quick summary of HTML and XHTML basics and gives some practical tips to make the most of your time as a web page author and publisher. It's not all theory, however; you do get to see a real web page and the HTML code behind it.

Here's a review of what you need to do before you're ready to use the rest of this book:

  1. Get a computer. I used a computer with Windows Vista to test the sample web content and capture the figures in this book, but you can use any Windows, Macintosh, or Linux/UNIX machine to create and view your web content.
  2. Get a connection to the Internet. Whether you have a dial-up, wireless, or broadband connection doesn't matter for the creation and viewing of your web content, but the faster the connection, the better for the overall experience. The Internet Service Provider (ISP), school, or business that provides your Internet connection can help you with the details of setting it up properly. Additionally, many public spaces such as coffee shops, bookstores, and libraries offer free wireless Internet service that you can use if you have a laptop computer with Wi-Fi network support.
  3. Get web browser software. This is the software your computer needs in order to retrieve and display web content. As you learned in the first hour, the most popular browser software (in alphabetical order) is Apple Safari, Google Chrome, Mozilla Firefox, Microsoft Internet Explorer, and Opera. It's a good idea to install several of these browsers so that you can experiment and make sure that your content looks consistent across them all; you can't make assumptions about the browsers other people are using.
  4. Explore! Use a web browser to look around the Internet for web sites that are similar in content or appearance to those you'd like to create. Note what frustrates you about some pages, what attracts you and keeps you reading others, and what makes you come back to some pages over and over again. If there is a particular topic that interests you, consider searching for it using a popular search engine such as Google (http://www.google.com/) or Bing (http://www.bing.com/).

Getting Started with a Simple Web Page

In the first hour, you learned that a "web page" is just a text file that is "marked-up" by (or surrounded by) HTML codes that tell the browser how to display the text. To create these text files, use a text editor such as Notepad (on Windows) or TextEdit (on a Mac)—do not use WordPad, Microsoft Word, or other full-featured word-processing software, as those create different sorts of files than the plain-text files we use for web content.

Before you begin working, you should start with some text that you want to put on a web page:

  1. Find (or write) a few paragraphs of text about yourself, your family, your company, your softball team, or some other subject in which you're interested.
  2. Save this text as plain, standard ASCII text. Notepad and most simple text editors always save files as plain text, but if you're using another program, you might need to choose this file type as an option (after selecting File, Save As).

As you go through this hour, you will add HTML markup (called tags) to the text file, thus making it into web content.

When you save files containing HTML tags, always give them a name ending in .html. This is important: if you forget to type the .html at the end of the filename when you save the file, most text editors will give it some other extension (such as .txt). If that happens, you might not be able to find the file when you try to look at it with a web browser; if you find it, it certainly won't display properly. In other words, web browsers expect a web page file to have a file extension of .html.

You might also encounter a web page with a file extension of .htm, which is also acceptable. You might find other file extensions used on the Web, such as .jsp (Java Server Pages), .asp (Microsoft Active Server Pages), or .php (PHP: Hypertext Preprocessor), but these file types use server-side technologies that are beyond the scope of HTML.

Listing 3.1 shows an example of text you can type and save to create a simple HTML page. If you opened this file with Firefox, you would see the page shown in Figure 3.1. Every web page you create must include the <html></html>, <head></head>, <title></title>, and <body></body> tag pairs.

Listing 3.1. The <html>, <head>, <title>, and <body> Tags

<?xml version="1.0" encoding="UTF-8"?>

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
    <title>The First Web Page</title>

      In the beginning, Tim created the HyperText Markup Language. The Internet
      was without form and void, and text was upon the face of the monitor and
      the Hands of Tim were moving over the face of the keyboard. And Tim said,
      Let there be links; and there were links. And Tim saw that the links were
      good; and Tim separated the links from the text. Tim called the links
      Anchors, and the text He called Other Stuff. And the whole thing together
      was the first Web Page.
Figure 3.1

Figure 3.1 When you save the text in as an HTML file and view it with a web browser, only the actual title and body text are displayed.

In Listing 3.1, as in every HTML page, the words starting with < and ending with > are actually coded commands. These coded commands are called HTML tags because they "tag" pieces of text and tell the web browser what kind of text it is. This allows the web browser to display the text appropriately.

The first few lines of code in the web page serve as standard boilerplate code that you will include in all of your pages. This code actually identifies the page as an XHTML 1.1 document, which means that, technically, the web page is an XHTML page. All the pages developed throughout the book are XHTML 1.1 pages. Because XHTML is a more structured version of HTML, it's still okay to generally refer to all the pages in the book as HTML pages. By targeting XHTML 1.1 with your code, you are developing web pages that adhere to the very latest web standards. This is a good thing!

If you have obtained a web hosting account, you could use FTP at this point to transfer the firstpage.html file to the web server. In fact, from this hour forward, the instructions will assume you have a hosting provider and are comfortable sending files back and forth via FTP; if that is not the case, please review the first two hours before moving on. Or, if you are consciously choosing to work with files locally (without a web host), be prepared to adjust the instructions to suit your particular needs (such as ignoring "transfer the files" and "type in the URL").

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