HTML5 MathML <mo> Tag

Definition and usage

The <mo> element holds an operator token. Browsers apply an operator dictionary that gives each symbol default spacing and behaviour. Attributes such as stretchy let brackets grow to the height of their content, fence marks a symbol as a bracket, and largeop enlarges operators like the summation sign in display mode.

Syntax

<mo stretchy="true" fence="true">(</mo>

Example

<math>
  <mrow>
    <mn>2</mn>
    <mo>+</mo>
    <mn>3</mn>
    <mo>=</mo>
    <mn>5</mn>
  </mrow>
</math>

Each <mo> holds an operator; the browser automatically spaces the + and = symbols correctly. When used as fences around tall content, stretchy operators grow to match the content's height.