An mo element represents an operator or anything that should be rendered as an operator. In MathML the list of things that should "render as an operator" includes a number of notations that are not mathematical operators in the ordinary sense. Besides ordinary operators with infix, prefix, or postfix forms, these include fence characters such as braces, parentheses, and "absolute value" bars; separators such as comma and semicolon; and mathematical accents such as a bar or tilde over a symbol. MathML Fundamentals
<math mathsize="40"> <mspace linebreak="newline" indentalign="center"></mspace> <mtext style="border:1px;" mathsize="50">Operators - arrows 1</mtext> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>21F6</mtext> <mrow> <mo style="border:1px">⇶</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⇶</mo> <mo style="border:1px" minsize="2" maxsize="2">⇶</mo> <mo style="border:1px" minsize="5">⇶</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>21FD</mtext> <mrow> <mo style="border:1px">⇽</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⇽</mo> <mo style="border:1px" minsize="2" maxsize="2">⇽</mo> <mo style="border:1px" minsize="5">⇽</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>21FE</mtext> <mrow> <mo style="border:1px">⇾</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⇾</mo> <mo style="border:1px" minsize="2" maxsize="2">⇾</mo> <mo style="border:1px" minsize="5">⇾</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>21FF</mtext> <mrow> <mo style="border:1px">⇿</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⇿</mo> <mo style="border:1px" minsize="2" maxsize="2">⇿</mo> <mo style="border:1px" minsize="5">⇿</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27F0</mtext> <mrow> <mo style="border:1px">⟰</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟰</mo> <mo style="border:1px" minsize="2" maxsize="2">⟰</mo> <mo style="border:1px" minsize="5">⟰</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>27F1</mtext> <mrow> <mo style="border:1px">⟱</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟱</mo> <mo style="border:1px" minsize="2" maxsize="2">⟱</mo> <mo style="border:1px" minsize="5">⟱</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>21F5</mtext> <mrow> <mo style="border:1px">⇵</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⇵</mo> <mo style="border:1px" minsize="2" maxsize="2">⇵</mo> <mo style="border:1px" minsize="5">⇵</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27F5</mtext> <mrow> <mo style="border:1px">⟵</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟵</mo> <mo style="border:1px" minsize="2" maxsize="2">⟵</mo> <mo style="border:1px" minsize="5">⟵</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27F6</mtext> <mrow> <mo style="border:1px">⟶</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟶</mo> <mo style="border:1px" minsize="2" maxsize="2">⟶</mo> <mo style="border:1px" minsize="5">⟶</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27F7</mtext> <mrow> <mo style="border:1px">⟷</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟷</mo> <mo style="border:1px" minsize="2" maxsize="2">⟷</mo> <mo style="border:1px" minsize="5">⟷</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27F8</mtext> <mrow> <mo style="border:1px">⟸</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟸</mo> <mo style="border:1px" minsize="2" maxsize="2">⟸</mo> <mo style="border:1px" minsize="5">⟸</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27F9</mtext> <mrow> <mo style="border:1px">⟹</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟹</mo> <mo style="border:1px" minsize="2" maxsize="2">⟹</mo> <mo style="border:1px" minsize="5">⟹</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27FA</mtext> <mrow> <mo style="border:1px">⟺</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟺</mo> <mo style="border:1px" minsize="2" maxsize="2">⟺</mo> <mo style="border:1px" minsize="5">⟺</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27FB</mtext> <mrow> <mo style="border:1px">⟻</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟻</mo> <mo style="border:1px" minsize="2" maxsize="2">⟻</mo> <mo style="border:1px" minsize="5">⟻</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27FC</mtext> <mrow> <mo style="border:1px">⟼</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟼</mo> <mo style="border:1px" minsize="2" maxsize="2">⟼</mo> <mo style="border:1px" minsize="5">⟼</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27FD</mtext> <mrow> <mo style="border:1px">⟽</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟽</mo> <mo style="border:1px" minsize="2" maxsize="2">⟽</mo> <mo style="border:1px" minsize="5">⟽</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>27FE</mtext> <mrow> <mo style="border:1px">⟾</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⟾</mo> <mo style="border:1px" minsize="2" maxsize="2">⟾</mo> <mo style="border:1px" minsize="5">⟾</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>290A</mtext> <mrow> <mo style="border:1px">⤊</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⤊</mo> <mo style="border:1px" minsize="2" maxsize="2">⤊</mo> <mo style="border:1px" minsize="5">⤊</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>290B</mtext> <mrow> <mo style="border:1px">⤋</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⤋</mo> <mo style="border:1px" minsize="2" maxsize="2">⤋</mo> <mo style="border:1px" minsize="5">⤋</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2912</mtext> <mrow> <mo style="border:1px">⤒</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⤒</mo> <mo style="border:1px" minsize="2" maxsize="2">⤒</mo> <mo style="border:1px" minsize="5">⤒</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2913</mtext> <mrow> <mo style="border:1px">⤓</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⤓</mo> <mo style="border:1px" minsize="2" maxsize="2">⤓</mo> <mo style="border:1px" minsize="5">⤓</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>294E</mtext> <mrow> <mo style="border:1px">⥎</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥎</mo> <mo style="border:1px" minsize="2" maxsize="2">⥎</mo> <mo style="border:1px" minsize="5">⥎</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2950</mtext> <mrow> <mo style="border:1px">⥐</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥐</mo> <mo style="border:1px" minsize="2" maxsize="2">⥐</mo> <mo style="border:1px" minsize="5">⥐</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>294F</mtext> <mrow> <mo style="border:1px">⥏</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥏</mo> <mo style="border:1px" minsize="2" maxsize="2">⥏</mo> <mo style="border:1px" minsize="5">⥏</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2951</mtext> <mrow> <mo style="border:1px">⥑</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥑</mo> <mo style="border:1px" minsize="2" maxsize="2">⥑</mo> <mo style="border:1px" minsize="5">⥑</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2954</mtext> <mrow> <mo style="border:1px">⥔</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥔</mo> <mo style="border:1px" minsize="2" maxsize="2">⥔</mo> <mo style="border:1px" minsize="5">⥔</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2955</mtext> <mrow> <mo style="border:1px">⥕</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥕</mo> <mo style="border:1px" minsize="2" maxsize="2">⥕</mo> <mo style="border:1px" minsize="5">⥕</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>2952</mtext> <mrow> <mo style="border:1px">⥒</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥒</mo> <mo style="border:1px" minsize="2" maxsize="2">⥒</mo> <mo style="border:1px" minsize="5">⥒</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2953</mtext> <mrow> <mo style="border:1px">⥓</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥓</mo> <mo style="border:1px" minsize="2" maxsize="2">⥓</mo> <mo style="border:1px" minsize="5">⥓</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>2956</mtext> <mrow> <mo style="border:1px">⥖</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥖</mo> <mo style="border:1px" minsize="2" maxsize="2">⥖</mo> <mo style="border:1px" minsize="5">⥖</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2957</mtext> <mrow> <mo style="border:1px">⥗</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥗</mo> <mo style="border:1px" minsize="2" maxsize="2">⥗</mo> <mo style="border:1px" minsize="5">⥗</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>2958</mtext> <mrow> <mo style="border:1px">⥘</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥘</mo> <mo style="border:1px" minsize="2" maxsize="2">⥘</mo> <mo style="border:1px" minsize="5">⥘</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2959</mtext> <mrow> <mo style="border:1px">⥙</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥙</mo> <mo style="border:1px" minsize="2" maxsize="2">⥙</mo> <mo style="border:1px" minsize="5">⥙</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>295C</mtext> <mrow> <mo style="border:1px">⥜</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥜</mo> <mo style="border:1px" minsize="2" maxsize="2">⥜</mo> <mo style="border:1px" minsize="5">⥜</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2960</mtext> <mrow> <mo style="border:1px">⥠</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥠</mo> <mo style="border:1px" minsize="2" maxsize="2">⥠</mo> <mo style="border:1px" minsize="5">⥠</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>295A</mtext> <mrow> <mo style="border:1px">⥚</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥚</mo> <mo style="border:1px" minsize="2" maxsize="2">⥚</mo> <mo style="border:1px" minsize="5">⥚</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>295B</mtext> <mrow> <mo style="border:1px">⥛</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥛</mo> <mo style="border:1px" minsize="2" maxsize="2">⥛</mo> <mo style="border:1px" minsize="5">⥛</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>295E</mtext> <mrow> <mo style="border:1px">⥞</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥞</mo> <mo style="border:1px" minsize="2" maxsize="2">⥞</mo> <mo style="border:1px" minsize="5">⥞</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>295F</mtext> <mrow> <mo style="border:1px">⥟</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥟</mo> <mo style="border:1px" minsize="2" maxsize="2">⥟</mo> <mo style="border:1px" minsize="5">⥟</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>295D</mtext> <mrow> <mo style="border:1px">⥝</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥝</mo> <mo style="border:1px" minsize="2" maxsize="2">⥝</mo> <mo style="border:1px" minsize="5">⥝</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>2961</mtext> <mrow> <mo style="border:1px">⥡</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥡</mo> <mo style="border:1px" minsize="2" maxsize="2">⥡</mo> <mo style="border:1px" minsize="5">⥡</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>296E</mtext> <mrow> <mo style="border:1px">⥮</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥮</mo> <mo style="border:1px" minsize="2" maxsize="2">⥮</mo> <mo style="border:1px" minsize="5">⥮</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>296F</mtext> <mrow> <mo style="border:1px">⥯</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⥯</mo> <mo style="border:1px" minsize="2" maxsize="2">⥯</mo> <mo style="border:1px" minsize="5">⥯</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>005E</mtext> <mrow> <mo style="border:1px">^</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">^</mo> <mo style="border:1px" minsize="2" maxsize="2">^</mo> <mo style="border:1px" minsize="5">^</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>030C</mtext> <mrow> <mo style="border:1px">̌</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">̌</mo> <mo style="border:1px" minsize="2" maxsize="2">̌</mo> <mo style="border:1px" minsize="5">̌</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>005F</mtext> <mrow> <mo style="border:1px">_</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">_</mo> <mo style="border:1px" minsize="2" maxsize="2">_</mo> <mo style="border:1px" minsize="5">_</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>007E</mtext> <mrow> <mo style="border:1px">~</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">~</mo> <mo style="border:1px" minsize="2" maxsize="2">~</mo> <mo style="border:1px" minsize="5">~</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>203E</mtext> <mrow> <mo style="border:1px">‾</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">‾</mo> <mo style="border:1px" minsize="2" maxsize="2">‾</mo> <mo style="border:1px" minsize="5">‾</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>23B4</mtext> <mrow> <mo style="border:1px">⎴</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⎴</mo> <mo style="border:1px" minsize="2" maxsize="2">⎴</mo> <mo style="border:1px" minsize="5">⎴</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>23B5</mtext> <mrow> <mo style="border:1px">⎵</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⎵</mo> <mo style="border:1px" minsize="2" maxsize="2">⎵</mo> <mo style="border:1px" minsize="5">⎵</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>23DC</mtext> <mrow> <mo style="border:1px">⏜</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⏜</mo> <mo style="border:1px" minsize="2" maxsize="2">⏜</mo> <mo style="border:1px" minsize="5">⏜</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>23DD</mtext> <mrow> <mo style="border:1px">⏝</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⏝</mo> <mo style="border:1px" minsize="2" maxsize="2">⏝</mo> <mo style="border:1px" minsize="5">⏝</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>23DE</mtext> <mrow> <mo style="border:1px">⏞</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⏞</mo> <mo style="border:1px" minsize="2" maxsize="2">⏞</mo> <mo style="border:1px" minsize="5">⏞</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>23DF</mtext> <mrow> <mo style="border:1px">⏟</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⏟</mo> <mo style="border:1px" minsize="2" maxsize="2">⏟</mo> <mo style="border:1px" minsize="5">⏟</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>23E0</mtext> <mrow> <mo style="border:1px">⏠</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⏠</mo> <mo style="border:1px" minsize="2" maxsize="2">⏠</mo> <mo style="border:1px" minsize="5">⏠</mo> </mrow> </mfrac> <mfrac style="border:1px"> <mtext>23E1</mtext> <mrow> <mo style="border:1px">⏡</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">⏡</mo> <mo style="border:1px" minsize="2" maxsize="2">⏡</mo> <mo style="border:1px" minsize="5">⏡</mo> </mrow> </mfrac> <mspace linebreak="newline" indentalign="center"></mspace> <mfrac style="border:1px"> <mtext>0644</mtext> <mrow> <mo style="border:1px">ل</mo> <mo style="border:1px" minsize="1.2" maxsize="1.2">ل</mo> <mo style="border:1px" minsize="2" maxsize="2">ل</mo> <mo style="border:1px" minsize="5">ل</mo> </mrow> </mfrac> </math>