W3Teacher Online Web Tutorials: HTML Attributes

Attributes provide additional information about HTML elements.

HTML Attributes

HTML elements can have attributes
Attributes provide additional information about an element
Attributes are always specified in the start tag
Attributes come in name/value pairs like: name="value"

The lang Attribute

The document language can be declared in the <html> tag.

The language is declared in the lang attribute.

Declaring a language is important for accessibility applications (screen readers) and search engines:

<!DOCTYPE html>
<html lang="en-US">
<body>

<h1>My First Heading</h1>
My first paragraph.

</body>
</html>

The first two letters specify the language (en). If there is a dialect, use two more letters (US).

The title Attribute

HTML paragraphs are defined with the tag.

In this example, the element has a title attribute. The value of the attribute is "About W3Teacher":

Example :

W3Teacher is a web developer's site.
It provides tutorials and references covering
many aspects of web programming,
including HTML, CSS, JavaScript, XML, SQL, PHP, ASP, etc.

Try it Yourself >>

When you move the mouse over the element, the title will be displayed as a tooltip.

The href Attribute

HTML links are defined with the <a> tag. The link address is specified in the href attribute:

Example :

Try it Yourself >>

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 :

Try it Yourself >>

The image size is specified in pixels: width="200" means 200 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 HTML element cannot be displayed.

The value of the attribute can be read by "screen readers". This way, someone "listening" to the webpage, i.e. a blind person, can "hear" the element.

Example :

Try it Yourself >>

We Suggest: Always Use Lowercase Attributes

The HTML5 standard does not require lower case attribute names.

The title attribute can be written with upper or lower case like Title and/or TITLE.

W3C recommends lowercase in HTML4, and demands lowercase for stricter document types like XHTML.

Lower case is the most common. Lower case is easier to type. At W3Teacher we always use lower case attribute names.

We Suggest: Always Quote Attribute Values

The HTML5 standard does not require quotes around attribute values. The href attribute, demonstrated above, can be written as:

Example :

Try it Yourself >>

W3C recommends quotes in HTML4, and demands quotes for stricter document types like XHTML. Sometimes it is necessary to use quotes. This will not display correctly, because it contains a space:

Example :

You cannot omit quotes around an attribute value
if the value contains spaces.

Try it Yourself >>

Using quotes are the most common. Omitting quotes can produce errors. At W3Teacher we always use quotes around attribute values.

Single or Double Quotes?

Double style quotes are the most common in HTML, but single style can also be used.

In some situations, when the attribute value itself contains double quotes, it is necessary to use single quotes:

Or vice versa: