Number

• Number()
• Math.ceil() - Round up Number
• Math.round() - Round to nearest integer
• String to Integer

Number()

• Converts the object argument to a number that represents the object's value. home If the value cannot be converted to a legal number, NaN is returned.

   var n1 = true;       Number(n1) => 1
   var n2 = false;      Number(n2) => 0
   var n3 = new Date(); Number(n3) => 17171717171788 //returns the number of milliseconds since midnight January 1, 1970 UTC.
   var n4 = "123";      Number(n4) => 123
   var n5 = "abc";      Number(n5) => NaN``

ceil()

• Rounds a number UPWARDS to the nearest integer, and returns the result. If the passed argument is an integer, the value will not be rounded.home

   Math.ceil()192.16) => 192.2

round()

• rounds a number to the nearest integer.home

   Math.round(2.49); => 2 //will rounded down to 2
   Math.round(2.5; => 3 //will rounded up to 3 

String-To-Integer

• replace() home

   var str = "2,222";
   str.replace(",",""); => 2222

• parseInt() function parses a string and returns an integer.

   var str = "2,222";
   parseInt(str); => 2222

• parseFloat() function parses a string and returns a floating point number.

   var str = "2,222.22";
   parseFloat(str); => 2222.22
   parseFloat(str).toFixed(1); => 222.2