display: block can change an element to be block instead of inline or other display types
margin: auto automatically centers a block item
position: fixed lets you manually choose locations for an element (check next line)
the top, left, right, and bottom attributes work with position: fixed to let you manually set how far away you want something from a direction.
<dl> is a description list for defining terms
<dt> is a description term to put in a description list
<dd> is a description definition to put with a description term
<datalist> is a tag similar to the select tag, but the user has the additional ability to type in the box to find something