Image source and alt attribute in HTML - Mini Project: Build & Apply

Image source and alt attribute

📖 Scenario: You are creating a simple webpage to display a picture of a cute puppy. This webpage will help visitors see the image and understand what it shows even if the image cannot load.

🎯 Goal: Build a basic HTML page that shows an image of a puppy using the correct src and alt attributes in the <img> tag.

📋 What You'll Learn

Use a valid HTML5 document structure with <!DOCTYPE html>, <html>, <head>, and <body> tags.

Add an <img> tag with the exact src attribute set to 'puppy.jpg'.

Add an alt attribute to the <img> tag with the text 'Cute puppy sitting on grass'.

Make sure the HTML is valid and the image displays correctly in a browser.

💡 Why This Matters

🌍 Real World

Websites use images to make content engaging and informative. Using the <code>alt</code> attribute helps people who use screen readers and improves SEO.

💼 Career

Knowing how to properly add images with descriptive alt text is a fundamental skill for web developers and content creators to build accessible and user-friendly websites.

1

Create the basic HTML structure

Write the basic HTML5 skeleton with <!DOCTYPE html>, <html lang="en">, <head> containing a <meta charset="UTF-8"> and <title>Puppy Image</title>, and an empty <body>.

HTML

    
    Puppy Image


    

Hint

Start by typing the standard HTML5 document tags and set the language to English.

2

Add the image tag with source

Inside the <body>, add an <img> tag with the src attribute set exactly to "puppy.jpg".

HTML

    
    Puppy Image


    

Hint

Use the <img> tag and set the src attribute to the image file name.

3

Add the alt attribute to the image

Modify the existing <img> tag to include an alt attribute with the exact text "Cute puppy sitting on grass".

HTML

    
    Puppy Image


    
    

Hint

The alt attribute describes the image for screen readers and when the image cannot load.

4

Complete the HTML document

Ensure the HTML document is properly closed with the closing </body> and </html> tags and that the <img> tag includes both src and alt attributes as specified.

HTML

    
    Puppy Image


    
    

Hint

Check that all tags are closed and the image tag has both required attributes.

Practice

1. What does the alt attribute in an <img> tag do?

easy

A. Provides a text description of the image for screen readers and when the image can't load

B. Specifies the URL of the image to display

C. Sets the size of the image on the page

D. Adds a border around the image

Solution

1. Step 1: Understand the purpose of the alt attribute

   The alt attribute provides alternative text describing the image content.

2. Step 2: Recognize its use for accessibility and fallback

   This text helps screen readers and shows if the image fails to load.

3. Final Answer:

   Provides a text description of the image for screen readers and when the image can't load -> Option A

4. Quick Check:

   alt describes image content [OK]

Hint: Alt text describes images for accessibility and fallback [OK]

Common Mistakes:

• Confusing alt with src attribute
• Thinking alt controls image size
• Using alt to add styling

2. Which of the following is the correct syntax to add an image with source "photo.jpg" and alt text "A sunset"?

easy

A.

B.

C.

D.

Solution

1. Step 1: Identify correct tag and attributes

   The correct tag is <img> with attributes src and alt.

2. Step 2: Check attribute names and order

   <img src="photo.jpg" alt="A sunset"> uses correct attribute names and syntax: src="photo.jpg" and alt="A sunset".

3. Final Answer:

   <img src="photo.jpg" alt="A sunset"> -> Option A

4. Quick Check:

   Correct tag and attributes = <img src="photo.jpg" alt="A sunset"> [OK]

Hint: Use <img> with src and alt attributes exactly named [OK]

Common Mistakes:

• Using <image> instead of <img>
• Using 'source' instead of 'src'
• Using 'description' instead of 'alt'

3. What will the browser display if this code is used and the image file "logo.png" is missing?

<img src="logo.png" alt="Company Logo">

medium

A. Nothing will show, just empty space

B. The browser will crash

C. An error message will pop up

D. The text "Company Logo" will appear instead of the image

Solution

1. Step 1: Understand what happens when image source is missing

   If the image file can't be found, the browser shows the alt text as a fallback.

2. Step 2: Identify the alt text in the code

   The alt text is "Company Logo", so this text will display in place of the missing image.

3. Final Answer:

   The text "Company Logo" will appear instead of the image -> Option D

4. Quick Check:

   Missing image shows alt text [OK]

Hint: Missing images show alt text in browser [OK]

Common Mistakes:

• Expecting no output or blank space
• Thinking browser shows error popups
• Assuming browser crashes

4. Find the error in this image tag:

<img src="picture.jpg" alt>

medium

A. The img tag should be closed with

B. The src attribute is misspelled

C. The alt attribute is missing a value

D. The alt attribute should be written as alt-text

Solution

1. Step 1: Check the alt attribute syntax

   The alt attribute is present but has no value assigned, which is invalid.

2. Step 2: Confirm correct attribute names and tag usage

   The src attribute is correct, and <img> is self-closing, so no closing tag needed.

3. Final Answer:

   The alt attribute is missing a value -> Option C

4. Quick Check:

   Alt attribute must have a value [OK]

Hint: Alt attribute always needs a descriptive value [OK]

Common Mistakes:

• Leaving alt attribute empty
• Adding closing tag
• Changing alt attribute name incorrectly

5. You want to add an image that shows a cat playing with a ball. Which is the best way to write the <img> tag for accessibility and SEO?

hard

A.

B.

C.

D.

Solution

1. Step 1: Understand the purpose of alt text for accessibility and SEO

   Alt text should clearly describe the image content to help screen readers and improve search engine understanding.

2. Step 2: Evaluate the options for descriptive quality

   <img src="cat-ball.jpg" alt="Cat playing with a ball"> describes the image specifically as "Cat playing with a ball", which is clear and meaningful.

3. Final Answer:

   <img src="cat-ball.jpg" alt="Cat playing with a ball"> -> Option B

4. Quick Check:

   Descriptive alt text improves accessibility and SEO [OK]

Hint: Use clear, specific alt text describing the image content [OK]

Common Mistakes:

• Using vague alt text like 'image' or 'cute'
• Omitting alt attribute entirely
• Using unrelated or too short alt text