Line Breaks
Like you saw in Using Spaced Paragraphs, if you want more control over how the contents of a paragraph appear, you can force a line break inside a paragraph using the break tag (<br />).
HTML
<p>This is the first line in the paragraph.
<br />
Using a line break element, this is a separate line in the same paragraph.</p>
Compare this to Markdown:
Markdown
This is the first line in the paragraph.
Separated by a single newline, this is a separate line in the same paragraph.
html