HTML5 elements are marked up using start tags and end tags. HTML5 Tags are delimited using angle brackets with the tag name in between.
The difference between start tags and end tags is that the latter includes a slash before the tag name.
Following is the example of an HTML5 element:
HTML5 tag names are case insensitive and may be written in all uppercase or mixed case, although the most common convention is to stick with lowercase.
Most of the elements contain some content like <p>…</p> contains a paragraph. Some elements, however, are forbidden from containing any content at all and these are known as void elements. For example, br, hr, link and meta etc