Also very effective to use on an entire page to keep things from getting too close to the edge. Use H1 or H2 or H3 etc. It automatically adds a paragraph break after the heading. Increases font size by the amount of the number. You can also use negative numbers.
Higher numbers are larger font size.
Changes font size to a specific size. You can change the font color within your text. You can change the actual font used to some extent within your text. The most annoying code in html. Within the pre-formatted tag, text and numbers, etc. will be lined up exactly as you typed them.