Block-Level Elements
A block-level element always starts on a new line.

• A generic container for block-level content.

• Headings.

• A paragraph.

• An unordered list.
• An ordered list.
• A list item (inside
  or
  ).
• A section of a document.
• An independent self-contained content.

Example:
index.html

<div>
  <h1>This is a Heading</h1>
  <p>This is a paragraph inside a div.</p>
</div>