Attributes provide additional information about HTML elements.
HTML Attributes
- All HTML elements can have attributes
- Attributes provide additional information about an element
- Attributes are always specified in the start tag
- Attributes usually come in name/value pairs like: name="value"
The href Attribute
HTML links are defined with the<a>
tag. The link address is specified in the href
attribute:Example
<a href="https://www.techzoonbd.com">This is a link</a>
<a>
tag later in this tutorial.The src Attribute
HTML images are defined with the<img>
tag.The filename of the image source is specified in the
src
attribute:Example
<img src="img_girl.jpg">
The width and height Attributes
Images in HTML have a set of size attributes, which specifies the width and height of the image:Example
<img src="img_girl.jpg" width="500" height="600">
The alt Attribute
Thealt
attribute specifies an alternative text to be used, when an
image cannot be displayed.The value of the attribute can be read by screen readers. This way, someone "listening" to the webpage, e.g. a blind person, can "hear" the element.
Example
<img src="img_girl.jpg" alt="Girl
with a jacket">
The
alt
attribute is also useful if the image does not exist:Example
See what happens if we try to display an image that does not exist:
<img src="img_typo.jpg" alt="Girl
with a jacket">
The style Attribute
Thestyle
attribute is used to specify the styling of an element, like color,
font, size etc.Example
<p style="color:red">I am a paragraph</p>
The lang Attribute
The language of the document can be declared in the<html>
tag.The language is declared with the
lang
attribute.Declaring a language is important for accessibility applications (screen readers) and search engines:
<!DOCTYPE html>
<html lang="en-US">
<body>
...
</body>
</html>
The title Attribute
Here, atitle
attribute is added to the <p>
element.
The value of the title attribute will be displayed as a tooltip when
you mouse over the paragraph:Example
<p title="I'm a tooltip">
This is a paragraph.
</p>
We Suggest: Quote Attribute Values
The HTML5 standard does not require quotes around attribute values.The
href
attribute, demonstrated above, can be written without quotes:Bad
<a
href=https://www.techzoonbd.com>
Good
<a href="https://www.techzoonbd.com">
Sometimes it is necessary to use quotes. This example will not display the title attribute correctly, because it contains a space:
Example
<p
title=About Techzoonbd>
Using quotes are the most common. Omitting quotes can produce errors.
At W3Schools we always use quotes around attribute values.
At W3Schools we always use quotes around attribute values.
Single or Double Quotes?
Double quotes around attribute values are the most common in HTML, but single quotes can also be used.In some situations, when the attribute value itself contains double quotes, it is necessary to use single quotes:
<p title='John "ShotGun" Nelson'>
<p title="John 'ShotGun' Nelson">
Chapter Summary
- All HTML elements can have attributes
- The
title
attribute provides additional "tool-tip" information - The
href
attribute provides address information for links - The
width
andheight
attributes provide size information for images - The
alt
attribute provides text for screen readers - At we always use lowercase attribute names
- At we always quote attribute values with double quotes
Test Yourself with Exercises!
HTML Attributes
Below is an alphabetical list of some attributes often used in HTML:Attribute | Description |
---|---|
alt | Specifies an alternative text for an image, when the image cannot be displayed |
disabled | Specifies that an input element should be disabled |
href | Specifies the URL (web address) for a link |
id | Specifies a unique id for an element |
src | Specifies the URL (web address) for an image |
style | Specifies an inline CSS style for an element |
title | Specifies extra information about an element (displayed as a tool tip) |
A complete list of all attributes for each HTML element, is listed in our:
HTML Attribute Reference.
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