reduce()

.reduce() reduces an array into one final value.

Use it when you want a total, maximum, minimum, grouped object, or combined result.

Total Example

const prices = [5, 30, 10, 25, 15, 20]
 
const total = prices.reduce((previous, next) => {
  return previous + next
}, 0)
 
console.log(`$${total.toFixed(2)}`)

Maximum Example

const grades = [56, 38, 90, 25, 15, 70]
const maximum = grades.reduce((max, grade) => Math.max(max, grade))
 
console.log(maximum) // 90