HTML Element Content Models
An HTML element's content model specifies what is allowed inside the element.
Content Model of <head> Tag
The expected content of the <head> tag consists of HTML elements categorized as metadata content elements. (In the HTML tag list, click on an HTML tag to see the content model of that element.)
Content Model of <body> Tag
The expected content of the <body> tag consists of HTML elements categorized as flow content elements. (In the HTML tag list, click on an HTML tag to see the content model of that element.)
Flow Content vs. Phrasing Content
When the expected content of an HTML element is flow content, you can code either flow content elements or phrasing content elements, with some occasional restrictions.
In other words, flow content elements can only be used where flow content is expected.
When the expected content of an HTML element is phrasing content, you cannot code any flow content elements, only phrasing content elements, with some occasional additional restrictions.
In other words, phrasing content elements can be used where either flow content or phrasing content is expected.