HTML Attributes

Objectives and Overview

This lesson provides an overview of HTML attributes. You’ll take a look at some common HTML attributes such as classes and ids. Additionally, this lesson contains examples of setting HTML attributes.

Lesson Objectives

  • Explain what an HTML attribute is and describe common uses.
  • Explain how to set attributes on HTML elements.

Introduction to HTML Attributes

Now that you’re familiar with HTML basics it’s time to dive a bit further in and start working with Attributes. Attributes are additional values that each HTML tag contain. These additional properties add additional configuration to the HTML elements or alter their behavior. Often, attributes are used to provide additional information about an element.

Defining Attributes

Attributes are defined within the opening tag of an element. An attribute consists of a name and a value. The attribute name is followed by an equals sign (=), then opening quotes (“), then the attribute’s value, and finally closing quotes (“).

Look at the following example of an anchor <a> element:

<a href="">Link to the Digital Harbor Foundation Website</a>
Code language: HTML, XML (xml)

The display text “Link to the Digital Harbor Foundation Website” is placed between the opening <a> and closing </a> anchor tags.

Common Attributes

There are lots of HTML attributes, but there are some that are far more commonly used than others.

Here is a list of the most commonly used attributes and their purpose:

  • id – Identifies an element.
  • class – Classifies an element.
  • src – Source of an embeddable content, typically an <img>
  • href – Hyperlink reference to linked content.
  • alt – Alternate text for an image.

Classes and Ids

Now that you’ve reviewed some of the HTML basics, it’s time to jump into one of the key HTML concepts used in combination with CSS and JavaScript: ids and classes. Ids and classes are commonly used as CSS selectors, a review of which will be covered in the next section. However, since the ids and classes are declared in the HTML, the review is going to be included in the HTML.

Setting These Attributes

The class of an element can be set in the following way:

<div class="image-container"></div>

The id of an element can be set in the following way:

<div id="hidden-content"></div>

Id attributes are even more precise than class attributes, as they target only one unique element at a time. Regardless of which type of element they appear on, id attribute values can only be used once per page.

While you’ll see ids being used for CSS, it’s typically considered a best practice to only use classes for CSS. You’ll want to reserve using id attributes for specific purposes, typically related to JavaScript interaction.