HTMLmarkup~10 mins

Avoiding deprecated tags in HTML - Browser Rendering Trace

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Render Flow - Avoiding deprecated tags

Read <html>

→Create HTML root node

↓

Read <body>

→Create BODY node

↓

Read <center>

→Create CENTER node

↓

Add text 'Hello World'

↓

Close CENTER

↓

Close BODY

↓

Close HTML

The browser reads the HTML tags in order, creates nodes for each element, and nests them according to the tag structure. Deprecated tags like <center> still create nodes but are discouraged.

Render Steps - 3 Steps

Code Added:<center>Hello World</center>

Before

[body]
  |
  +-- (empty space)

Text is left aligned by default.

→

After

[body]
  |
  +-- [center]
        |
        +-- Hello World (centered horizontally)

Text is visually centered horizontally inside the body.

The <center> tag centers its content horizontally by default, changing the text alignment from left to center.

🔧 Browser Action:Creates CENTER element node and applies default centering style.

Code Sample

This code shows text centered using the deprecated <center> tag, which visually centers the text but is not recommended.

HTML

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Deprecated Tags Example</title>
</head>
<body>
  <center>Hello World</center>
</body>
</html>

HTML

body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  font-family: Arial, sans-serif;
}

Render Quiz - 3 Questions

Test your understanding

After applying step 1, how is the text 'Hello World' positioned?

ACentered vertically only

BAligned to the left by default

CCentered horizontally inside the body

DCentered both horizontally and vertically

Common Confusions - 3 Topics

Why does my <center> tag still work even though it's deprecated?

Browsers keep supporting deprecated tags like <center> for backward compatibility, so it still centers content visually but should not be used in new code.

💡 Deprecated tags may still show effects but modern CSS is the correct way to style.

Why doesn't text-align: center center my block element vertically?

text-align: center only centers inline content horizontally. Vertical centering requires other CSS like flexbox or grid (see render_step 2).

💡 Use flexbox for vertical and horizontal centering, not text-align alone.

If I remove <center> without CSS, why does my text shift left?

Without <center> or CSS centering, text defaults to left alignment (render_step 3). You must add CSS to keep it centered.

💡 Centering requires either HTML tag or CSS; removing one needs replacing with the other.

Property Reference

Tag/Property	Type	Default Behavior	Visual Effect	Recommended Use
<center>	HTML tag	Centers content horizontally	Centers text horizontally	Avoid; use CSS instead
text-align: center;	CSS property	Centers inline content horizontally	Centers text horizontally	Use for inline text centering
display: flex;	CSS property	Creates flex container	Enables flexible layout	Use for modern layout control
justify-content: center;	CSS property	Aligns flex items horizontally	Centers items horizontally	Use with flex containers
align-items: center;	CSS property	Aligns flex items vertically	Centers items vertically	Use with flex containers

Concept Snapshot

<center> tag centers text horizontally but is deprecated. Use CSS properties like display:flex, justify-content, and align-items for modern centering. text-align:center centers inline text horizontally only. Removing deprecated tags improves accessibility and future-proofs code. Flexbox can center content both horizontally and vertically.