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 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 first two letters specify the language (en). If there is
a dialect, use two more letters (US).
The title Attribute
Here, a title 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>
»
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.Omegas.com">This
is a link</a>
»
You will learn more about links and the <a> tag later
in this tutorial.
Size Attributes
HTML images are defined with the <img> tag.
The filename of the source (src), and the size of the image
(width and height) are all provided as attributes:
Example
<img src="Omegas.jpg"
width="104" height="142">
»
The image size is specified in pixels: width="104"
means 104 screen pixels wide.
You will learn more about images and the <img> tag
later in this tutorial.
The alt Attribute
The alt 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="Omegas.jpg"
alt="Omegas.com" width="104" height="142">
»
We Suggest: Use Lowercase Attributes
The HTML5 standard does not require lowercase attribute
names.
The title attribute can be written with uppercase or
lowercase like title or TITLE.
We Suggest: Quote Attribute Values
The HTML5 standard does not require quotes around attribute
values.
The href attribute, demonstrated above, can be written as:
Example
<a href=https://www.Omegas.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 Omegas>
»
Using quotes are the most common. Omitting quotes can produce
errors.
At Omegas 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'>
Or vice versa:
<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 and height attributes provide size information for
images
The alt attribute provides text for screen readers
At Omegas we always use lowercase attribute names
At Omegas 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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