There are six levels of headings, from <h1> to <h6>. The larger the number, the smaller the text.
html:
<h1>This is a Heading 1</h1>

<h2>This is a Heading 2</h2>

Use the <p> tag to create paragraphs.
html:
<p>This is a paragraph of text.</p>

Use <b> for bold text and <i> for italic text.
html:
<b>This is bold text.</b>

<i>This is italic text.</i>

Use ordered (<ol>) or unordered (<ul>) lists to organize items.
html:
<ul>

  <li>Item 1</li>

  <li>Item 2</li>

</ul>