Expressions

JavaScript expressions

Expressions are anything JavaScript can evaluate to a value, including undefined and null.

Examples:

> 7 + (5 + 2)
= 14

> console.log(5 + 2)
7
= undefined

Note that without a return value, expressions return undefined. Console.log() outputs to a console but doesn't return anything, hence undefined.

Any value is an expression that evaluates to itself.