Make a hash out of thin air!

ThinAirHash.js

/*
>>>>>>>>>>>>>>>>>
ThinAirHash
>>>>>>>>>>>>>>>>>

use:
	makeHash(length);
returns:
	random hash consisting of up/lowercase letters and numbers 0-9

*/

function makeHash(length){
	var hash = "";
	var letters = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"];
	for(var c=0; c<length; c++){
		var whichone = Math.round(Math.random()*1);
		if(whichone == 0){
			var char = Math.round(Math.random()*9);
		}
		if(whichone == 1){
			var char = letters[Math.round(Math.random()*50)];
		}
		hash = hash + String(char);
	}
	return hash;
}