HTML Basics for DHTML - Tutorial

HTML (Hypertext Markup Language) is a fundamental component of DHTML (Dynamic HTML) development. It forms the structure and content of web pages. In this tutorial, we will cover the basics of HTML and explore the essential tags and elements that are vital for DHTML.

Understanding HTML Structure

HTML follows a hierarchical structure composed of tags and elements. Tags define the beginning and end of elements, while elements encapsulate content within the tags. Let's look at an example:


<!DOCTYPE html>
<html>
<head>
  <title>My Web Page</title>
</head>
<body>
  <h1>Welcome to My Web Page!</h1>
  <p>This is a sample paragraph.</p>
</body>
</html>

In the example above, we have a basic HTML structure. The <!DOCTYPE html> declaration specifies the document type as HTML5. The <html> tag is the root element, and it contains two main sections: <head> and <body>. The <head> section contains meta information and the page title, while the <body> section contains the visible content of the web page.

Common HTML Tags and Elements

HTML provides various tags and elements to structure and organize web content. Here are some commonly used ones:

<h1> - <h6>: Heading tags define different levels of headings, with <h1> being the highest and <h6> being the lowest.
<p>: The <p> tag represents a paragraph of text.
<a>: The <a> tag creates a hyperlink, allowing users to navigate to other web pages or specific sections within a page.
<img>: The <img> tag inserts an image into the web page.
<ul> and <li>: The <ul> tag creates an unordered list, and the <li> tag defines each list item.
<div>: The <div> tag is a container used to group and style HTML elements.

Common Mistakes with HTML for DHTML

Forgetting to close tags, resulting in invalid HTML structure.
Overusing or misusing heading tags, leading to incorrect document structure and poor accessibility.
Not providing alternative text for images, which is essential for accessibility and search engine optimization (SEO).

Frequently Asked Questions

1. Can I create a web page with only the <body> tag?

No, a web page must have a complete HTML structure, including the <html>, <head>, and <body> tags. The <head> section contains important meta information, such as the page title and links to external stylesheets and scripts.

2. How do I add links to other web pages using the <a> tag?

To add a link to another web page, you need to specify the URL within the href attribute of the <a> tag. For example: <a href="https://www.example.com">Link to Example</a>.

3. Can I nest HTML elements inside each other?

Yes, HTML elements can be nested within each other. However, it is important to maintain proper structure and ensure that tags are closed in the correct order to avoid invalid HTML.

4. What is the purpose of the <div> tag?

The <div> tag is a versatile container used to group and style HTML elements. It helps organize and structure content within a web page, making it easier to apply CSS styles or manipulate elements with JavaScript.

5. Can I use custom tags in HTML?

While HTML5 introduced the ability to create custom tags, it is generally recommended to avoid using them for compatibility and maintainability reasons. Instead, consider using semantic HTML elements or adding custom classes to existing elements.

Summary

HTML forms the foundation of DHTML development, providing the structure and content of web pages. By understanding HTML's hierarchical structure and using essential tags and elements, developers can create well-organized and structured web content. Avoiding common mistakes and following best practices ensures valid HTML and contributes to better accessibility and SEO.