One way to divide documents into sections is by using rules. The <HR> tag inserts a rule completely across the screen. The rule will break the copy where ever inserted. It will appear black and scale to the same width as the browser window.
Another way to divide documents into sections is by using graphics as rules. You make the graphic rule in a paint program and insert it with the <IMG> tag. Graphic rules do not change width when the browser screen is resized. The rule will not break the copy unless you use the <P> or <BR> tags.
Other ways to control rules are by width and alignment and percentage.
size
and shading