Element attributes are a powerful means of controlling the built-in settings of individual block and inline elements. They’re also used to apply user-defined behavior and supplemental information, such as citation information and fallback content, to certain elements.
Element attributes define the built-in and user-defined styles, behavior, and metadata that are applied to an individual block element or inline element in a document.
Declare the ID of an element
Turn on or turn off an individual element’s built-in features
Configure the built-in features of an individual element
Apply user-defined information, such as citation metadata, fallback text, link text, and target content, to an individual element
Apply user-defined roles and behaviors to an individual element
Element attributes are classified as positional or named. They’re set and defined directly on the element they’re modifying using an attribute list.
Attributes are assigned to block and inline elements using an attribute list.