var

The HTML <var> element marks a variable in a mathematical expression, program, or other technical explanation. It identifies a value that can change.

What you will learn

What changing value or variable var represents
How to use it in mathematical and programming examples
How it differs from code and samp

Basic mathematical example

<p>The area is <var>w</var> × <var>h</var>.</p>

The letters w and h represent values that can change. Use surrounding text to explain what each variable means.

Programming example

<p>The loop runs while <var>count</var> is less than the limit.</p>

var describes the role of a name in the explanation; it does not declare a variable or execute code. The actual declaration belongs in a code example, not in the HTML semantics.

var, code, and samp are different

var: A variable or placeholder whose value may change.
code: A fragment of program source or code-like syntax.
samp: Output produced by a program or system.

<p>Set <var>count</var> in the <code>for</code> loop.</p>
<p>The result is <samp>42</samp>.</p>

Explain variables clearly

A variable without context is difficult to understand. Introduce its meaning, units, allowed range, or relationship to other variables. For a long formula, a list or a separate explanation may be clearer than a dense inline sentence.

Common mistakes

Using var for every identifier in a code sample.
Expecting it to define or change a JavaScript variable.
Using it for program output instead of samp.
Marking a symbol without explaining what its value represents.