JavaScript has some built-in functions that accept a list of individuals arguments, but passing an array doen't work.

`Math.max`

, `Math.min`

are some of them.They are used to find the biggest and smallest numbers in the passed arguments, repectively.

Math.max(1, 2, 3, 4); // 4// Doesn't work because it treats the array as a single parameter// That parameter isn't a number, so the function returns `NaN`Math.max([1, 2, 3, 4]); // NaN

If we want to pass a dynamic array of numbers, then the ES6 spread operator (

`...`

) can help. It turns a varible to a list of individual parameters:const array = [1, 2, 3, 4];Math.max(...array); // 4

JavaScript engines implemented by different browsers have the limited number of parameters. Using the

`...`

operator doesn't work if you have a big array. Using the `reduce`

method doesn't have this problem.const max = (arr) => arr.reduce((a, b) => Math.max(a, b));max([1, 2, 3, 4]); // 4