typeof-number-and-NaN-in-JavaScript.js

console.log(typeof 37) // "number"
console.log(typeof 2.71828) // "number"
console.log(typeof Math.E) // "number"
console.log(typeof Infinity) // "number"

// The typeof NaN is "number" even though NaN means "Not-A-Number":
console.log(typeof NaN) // "number"

// Calling Number explicitly is one way to parse a number:
console.log(typeof Number(`1`)) // "number"

// The parseInt and parseFloat functions are other ways to parse:
console.log(typeof parseInt(`100`)) // "number"
console.log(typeof parseFloat(`100.01`)) // "number" 

// Parse failures lead to NaN, and NaN poisons other math:
console.log(typeof (2 * parseInt(`invalid`))) // "number"