HTML: the Root Element

What is Root Element

• Root element of HTML is the element represented by the html tag.
• Root element of XML may be other, depending on the XML. e.g. root element of SVG is represented by the svg tag. 〔see Practical SVG Tutorial〕
• Root element of Atom Webfeed is feed.

Why is Root Element Important

It's important because many CSS's meaning refers to it.

For example:

• Length Unit rem refers to root element.
• Position Property refers to root element.