HTML abbr tag
The <abbr> tag defines an abbreviation or an acronym, like “HTML”, “CSS”, “Mr.”. Use the title attribute to show the description for the abbreviation when you mouse over the element:
<abbr title="Cascading Style Sheets">CSS</abbr>
<abbr> can also be used with <dfn> to define an abbreviation:
<p><dfn><abbr title="Cascading Style Sheets">CSS</abbr>
</dfn> describes the style of an HTML document.</p>
You can style abbr tag like this:
abbr {
text-decoration: underline red dotted;
color: red;
}
abbr:hover {
cursor: help;
}