abbr element
If you don't know what an element is or how you must use it, I recommend you read the "HTML tags and attributes" tutorial that you can find in the HTML tutorials section.
Table of contents
Description
The abbr element represents an abbreviated term or acronym, possibly explained with the title attribute. If the title attribute is present, it must provide the expanded version of the abbreviation.
User agents will commonly render a tool tip, with the value of the title attribute, whenever the user puts the mouse over the element. This behavior, despite how useful it becomes in this case, is common to all elements.
The use of abbr to mark abbreviations isn't mandatory. Authors may use other methods to explain abbreviations, like providing the expanded version next to them in parenthesis.
In previous versions of the standard, acronyms would be represented by the acronym element. In HTML5 this element has been eliminated in favor of abbr.
Examples
The following example shows the abbr element being used to abbreviate a word. You'll be able to see the explanation by placing your mouse over the content of the element.
<p><abbr title="Professor">Prof.</abbr> Jhon Smith studied at the Guildhall School of Music and Drama.</p>
Prof. Jhon Smith studied at the Guildhall School of Music and Drama.
Now, the abbr element is used to explain an acronym.
<p><abbr title="International Organization for Standardization">ISO</abbr> is the world's largest developer of voluntary International Standards.</p>
ISO is the world's largest developer of voluntary International Standards.
Lastly, an examples of an abbreviation explained without using the abbr element.
<p>The president of the WB (World Bank) is, traditionally, an American...</p>
The president of the WB (World Bank) is, traditionally, an American...
Attributes
Global attributes
For information about global attributes refer to this list of global attributes in HTML5.
Events
Global events
For information about global events refer to this list of global events in HTML5.