Tooltips are labels that appear on hover and focus when the user hovers over an element with the cursor, focuses on an element using a keyboard (usually through the tab key), or upon touch (without releasing) in a touch UI.

Examples:

HTML Code:

<button type="button" class="btn btn-raised btn-default-bright" data-toggle="tooltip" data-placement="top" data-container="body" title="Top Tooltip">Top</button>
<button type="button" class="btn btn-raised btn-default-bright" data-toggle="tooltip" data-placement="bottom" data-container="body" title="Bottom Tooltip">Bottom</button>
<button type="button" class="btn btn-raised btn-default-bright" data-toggle="tooltip" data-placement="left" data-container="body" title="Left Tooltip">Left</button>
<button type="button" class="btn btn-raised btn-default-bright" data-toggle="tooltip" data-placement="right" data-container="body" title="Right Tooltip">Right</button>