html basics for web development

HTML Basics for Web Development

Introduction

HTML (HyperText Markup Language) is the standard markup language used to create web pages in web development. It defines the structure and content of a web page. This guide will help you to learn about html basics for web development.

Structure of an HTML Document

An HTML document is structured using several key elements:

				
					<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document Title</title>
</head>
<body>
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</html>
				
			
  • <!DOCTYPE html>: Declares the document type and version of HTML.
  • <html>: Root element that wraps the entire content of the page.
  • <head>: Contains meta-information about the document, such as charset, viewport settings, and the page title.
  • <body>: Contains the visible content of the page, such as text, images, links, etc.

HTML Elements and Tags

HTML elements are represented by tags that define the structure and content of the document. Basic tags include:

  • <h1> to <h6>: Heading tags for different levels of headings.
  • <p>: Paragraph tag for text content.
  • <a>: Anchor tag for creating links.
  • <img>: Image tag for embedding images.
  • <ul> and <ol>: Lists tags for unordered and ordered lists.
  • <li>: List item tag used within <ul> or <ol>.
  • <button>: Button tags for creating buttons.

Attributes in HTML

HTML tags can have attributes that provide additional information about an element. Some common attributes include:

  • class: Specifies one or more class names for an element (used for styling with CSS).
  • id: Specifies a unique id for an element (used for scripting or styling).
  • src: Specifies the URL of an image source in <img> tag.
  • href: Specifies the URL of the link destination in <a> tag.

Formatting Text and Headings

HTML provides various tags for text formatting and headings:

  • Headings: <h1> to <h6> for different levels of headings.
  • Text Formatting: <em>, <strong>, <b>, <i>, <u> for emphasis, strong emphasis, bold, italic, and underline respectively.
Formatting Text and Headings in HTML

Lists and Tables

Example: Creating an Unordered List

				
					<ul>
    <li>Item 1</li>
    <li>Item 2</li>
    <li>Item 3</li>
</ul>
				
			

Example: Creating a Simple Table

				
					<table>
    <tr>
        <th>Name</th>
        <th>Age</th>
    </tr>
    <tr>
        <td>User1</td>
        <td>25</td>
    </tr>
    <tr>
        <td>User2</td>
        <td>30</td>
    </tr>
</table>
				
			

Forms in HTML

Forms are used to collect user input in a web page. A form contains form controls like text fields, radio buttons, checkboxes, and submit buttons.
Example: Creating a Simple Form

				
					<form action="/submit-form" method="POST">
    <label for="name">Name:</label>
    <input type="text" id="name" name="name" required><br><br>

    <label for="email">Email:</label>
    <input type="email" id="email" name="email" required><br><br>

    <label for="gender">Gender:</label><br>
    <input type="radio" id="male" name="gender" value="male">
    <label for="male">Male</label><br>
    <input type="radio" id="female" name="gender" value="female">
 <label for="female">Female</label><br><br>

    <label for="hobbies">Hobbies:</label><br>
    <input type="checkbox" id="hobby1" name="hobbies" value="reading">
    <label for="hobby1">Reading</label><br>
    <input type="checkbox" id="hobby2" name="hobbies" value="traveling">
    <label for="hobby2">Traveling</label><br><br>
    
    <label for="country"> Country: </label>
    <select id="country" name="country">
        <option value = "country1"> Country1 </option>
        <option value="country2"> Country2 </option>
        <option value="country3"> Country3 </option>
    </select><br><br>
 <input type="submit" value="Submit">
</form>
				
			
  • <form>: The container for form controls. The action attribute defines where the form data is sent, and method specifies how the data is sent (GET or POST)
  • <label>: Associates a label with a form control
  • <input>: Used for various types of user input (text, email, radio, checkbox, submit).
  • <select>: Drop-down list for selecting an option
  • <textarea>: Multi-line text input field.
Input Types in Forms

Forms in HTML support various input types:

  • Text Input: <input type=”text”>
  • Password: <input type=”password”>
  • Email: <input type=”email”>
  • Number: <input type=”number”>
  • Radio Buttons: <input type=”radio”>
  • Checkboxes: <input type=”checkbox”>
  • Date: <input type=”date”>
  • File Upload: <input type=”file”>
  • Submit Button: <input type=”submit”>

Embedding Audio and Video

HTML5 introduced the ability to embed audio and video content directly into web pages using the <audio> and <video> tags.

  • <audio>: The container for audio content. The controls attribute adds play, pause, and volume controls.
  • <video>: The container for video content. The controls attribute adds play, pause, and volume controls. The width attribute sets the width of the video.
Attributes for Audio and Video

Both audio and video tags support various attributes:

  • controls: Adds controls for play, pause, and volume.
  • autoplay: Starts playing the media as soon as it is loaded.
  • loop: Replays the media automatically when it ends.
  • muted: Mutes the audio by default.

Semantic HTML

Semantic HTML tags provide meaning to the content they wrap, making the structure of the document more understandable for both developers and browsers. These tags also improve accessibility and SEO.

Semantic tags in html
Key Semantic Tags
  • <header>: Represents the header section of a document or a section, typically containing introductory content or navigational links.
  • <nav>: Represents a section of the document intended for navigation.
  • <section>: Defines a section in a document, often with a thematic grouping of content.
  • <article>: Represents a self-contained segment of content that could be independently distributed or reused, such as a blog post, article, or news story.
  • <aside>: Represents content that is tangentially related to the main content, such as sidebars or pull quotes.
  • <footer>: Represents the footer section of a document or a section, typically containing copyright information, links to terms of service, etc.
  • <main>: Represents the main content of the document, excluding content that is repeated across pages such as sidebars, navigation links, etc.
  • <figure>: Represents self-contained content, such as images, diagrams, or illustrations, that is usually accompanied by a caption.
  • <figcaption>: Used to provide a caption for the content within a <figure>.
Importance of Semantic Tags

Semantic tags are essential for several reasons:

  • Improved Accessibility: Screen readers and other assistive technologies can better interpret and navigate the content.
  • Better SEO: Search engines can more accurately understand the structure and context of your content, which can improve search rankings.
  • Maintainable Code: Code becomes more readable and easier to maintain, especially in larger projects.