Welcome to Learning HTML
The hgroup element allows you to treat multiple header elements as a single item without affecting the outline of your HTML document.
The h1 element represents a heading. HTML defines a hierarchy of heading elements, with h1 being the highest ranked. The other heading elements are h2, h3, through to h6.
You use three elements to define description lists: the dl, dt, and dd elements.
The li element denotes an item in a list. You can use it with the ul, ol, and menu elements (the menu element is not yet supported in the main stream browsers).
You use the ul element to denote unordered lists. As with the ol element, items in the ul element are denoted using the li element.