Which characters need to be escaped in HTML?

In HTML, certain characters have special meanings because they are part of the markup language. If you use them directly in your content, the browser might misinterpret them as code instead of plain text. To avoid this, these characters need to be escaped (converted into HTML entities), so they are displayed correctly on the page.

Common Characters That Need Escaping:

• < (less than) → Used to start a tag.
  
•  Escape as <
  
• > (greater than) → Used to close a tag.
  
•  Escape as >
  
• & (ampersand) → Used in entity declarations.
  
•  Escape as &
  
• " (double quote) → Used to define attribute values.
  
•  Escape as "
  
• ' (single quote) → Used in attribute values (less common but recommended).
  
•  Escape as '
  

Example:

If you write:

  5 < 10> 5

The browser may misinterpret it as invalid HTML. Instead, escape the symbols:

  5 < 10> 5

Now it displays correctly as: 5 < 10> 5.

Key Points:

• Escaping ensures that special symbols are displayed as text, not as HTML code.
  
• It’s especially important when displaying user-generated content to prevent XSS (Cross-Site Scripting) vulnerabilities.
  
• Most templating engines and frameworks automatically handle escaping, but it’s good to know when writing raw HTML.
  

In short, escaping special characters in HTML is essential for both correct rendering and web security.