Core Web Concepts
Intro to HTML Basics
HTML, or Hypertext Markup Language, is the standard language used for creating and formatting web pages. It is the foundation of all websites, providing the structure and content for web pages.
HTML is made up of a series of elements, or tags, that are placed within angle brackets (< and >) to indicate the purpose of a piece of content. These elements are typically used in pairs, with an opening and closing tag. For example, the element for a paragraph is <p> and the closing tag is </p>.
In addition to the content of a web page, HTML also includes a number of attributes that can be used to further specify the behavior of an element. These attributes are added to the opening tag of an element, and provide additional information about how the element should be displayed.
One of the most important elements in HTML is the <head> element, which is used to contain information about the page, such as the page title and any linked stylesheets or scripts. The <body> element is used to contain the main content of the page, such as text, images, and other media.
HTML also includes a number of other common elements, such as <h1> for headings, <a> for links, <img> for images, and <table> for tables. These elements are used to add structure and organization to the content of a web page.
In recent years, HTML has undergone a number of updates and improvements, with the latest version being HTML5. This version includes new elements and attributes that make it easier to create modern, responsive web pages that are optimized for mobile devices.
One of the key features of HTML5 is the ability to create semantic markup, which helps to improve the accessibility and searchability of a web page. This is achieved by using elements that accurately describe the content they contain, such as <header>, <nav>, and <footer> for common page elements, and <article> and <section> for organizing content.
Furthermore, HTML5 also includes new features for multimedia, such as the <audio> and <video> elements for embedding audio and video content, and the <canvas> element for creating dynamic, interactive graphics.
HTML is an essential part of the web, providing the basic structure and content for all web pages. With a strong understanding of HTML, developers can create well-structured and effective web pages that are easy for users to navigate and interact with. By staying up-to-date with the latest HTML techniques and best practices, developers can create web pages that are optimized for a wide range of devices and provide a great user experience.
How Does HTML Work?
HTML works by defining a series of elements, or tags, that are placed within angle brackets to indicate the purpose of a piece of content. These elements are used to structure and organize the content of a web page, providing a framework for the page's content and layout.
When a web browser loads a web page, it parses the HTML code and uses the elements to determine how the page should be displayed. The browser then renders the page on the user's screen, displaying the content and layout according to the HTML code.
Here's an example:
<!DOCTYPE html>
<html>
<head>
<title>My Web Page</title>
</head>
<body>
<h1>Welcome to My Web Page</h1>
<p>This is my first web page, created using HTML.</p>
<img src="my-image.jpg" alt="A picture of me" />
</body>
</html>
In this example, the <!DOCTYPE html> declaration indicates that the page is written in HTML5. The <html> element is the root element of the page, and contains the <head> and <body> elements.
The <head> element is used to contain information about the page, such as the page title. The <body> element contains the main content of the page, including the heading, paragraph, and image.
The <h1> element is used for the page heading, and the <p> element is used for the paragraph. The <img> element is used to embed an image, and the src attribute is used to specify the location of the image file. The alt attribute is used to provide a text alternative for the image, which is useful for users with visual impairments.
Good Semantics and Validating HTML
Semantics refers to the meaning and purpose of a piece of content in HTML. In HTML5, the use of semantic markup is emphasized, which involves using elements that accurately describe the content they contain. This helps to improve the accessibility and searchability of a web page, as the meaning and purpose of the content is clearly indicated to users and search engines.
For example, instead of using a generic <div> element to contain a page header, the <header> element can be used, which accurately describes the content it contains. This not only helps users understand the purpose of the content, but it also helps search engines index and rank the page more accurately.
In addition to using semantic markup, it is also important to validate HTML code to ensure that it is free of errors and follows the latest standards. This can be done using a number of online tools, such as the W3C Markup Validation Service, which checks a web page for compliance with HTML standards.
By using semantic markup and regularly validating HTML code, developers can create web pages that are more accessible and searchable, and that provide a better user experience.
Accessibility
Screen readers and other accessibility tools work with HTML by interpreting the elements and attributes of a web page to provide a usable and accessible experience for users with disabilities.
When a screen reader or accessibility tool encounters an HTML element, it uses the element's name and attributes to determine how the content should be presented to the user. For example, when a screen reader encounters a heading element, it will announce the heading text and indicate its level (e.g. "Heading level 1: Welcome to My Web Page").
Along with interpreting the elements of a web page, accessibility tools also use the attributes of an element to provide additional information and context. For example, the alt attribute of an <img> element can be used to provide a text alternative for an image, which is read aloud by a screen reader for users with visual impairments.
By using semantic markup and properly labeling and organizing content, developers can create web pages that are accessible and usable by a wide range of users, regardless of their abilities.