Sometimes you got passed an object in a function, and you need to check if this is an array.

Maybe if it’s an array you perform some operation, and if it’s not an array you perform something else.

How can you determine if an object is an array?

Use the isArray() static method provided by the Array built-in object, introduced in ECMAScript 5:

const list = [1, 2, 3]
Array.isArray(list) //true