Js + ES6

The function object has a length property set to the number of formal parameters it is declared with.
In JavaScript, variables don't have types -- values have types. 
The typeof operator always returns a string
Variables that have no value = "undefined", an "undeclared" variable is one that has not been formally declared in the accessible scope.
The typeof operator returns "undefined" even for "undeclared" (or "not defined") variables


let a = 13.6 | 0;[ floor float numbers]
  All bitwise operations except unsigned right shift, >>>, work on signed 32-bit integers. So using bitwise operations will 
  convert a float to an integer. - slightly faster than Math.floor - 32-bit signed integers only