In Author view, the amount of displayed markup can be controlled using the following dedicated actions:
The default tags display mode can be configured in the Author options page. However, if the document opened in Author editor does not have an associated CSS stylesheet, then the Full Tags mode will be used.
Block-level elements are those elements of the source document that are formatted visually as blocks (e. g. paragraphs), while the inline level elements are distributed in lines (e. g. emphasizing pieces of text within a paragraph, inline images, etc). The graphical format of the elements is controlled from the CSS sources via the display property.