∅

Empty set

Math

Named Entity

&empty;

Numeric Code

&#8709;

HTML Example (Named Entity)

<p>This is the Empty set: &empty;</p>

Output: This is the Empty set: ∅

HTML Example (Numeric Code)

<p>This is the Empty set: &#8709;</p>

Output: This is the Empty set: ∅

JavaScript Example

const char = "&empty;";
console.log(char); // ∅

Mathematical symbols should use entity codes for proper display in HTML, especially in scientific or technical content.

For all (universal quantifier)

There exists (existential quantifier)

Nabla (del operator)