Did you know that not all numbers are alike?  It turns out there are types of numbers.  Who knew.  So, what determines the type of a number?  Well, it has a lot to do with how they are used.  If the numbers are being used for counting, they must be positive integers and they are called natural numbers.  Oh, by the way, an integer is a number that is a whole number like 1 or 2 and does not have a decimal part or does not have to be represented as a fraction.  Speaking of fractions, if you do have to use a fraction to represent a number, that number is a real number.  These types of numbers come up a lot when you are trying to measure real physical things such as how much something weighs.  I don’t weight 160 lbs, I weigh 159.99 lbs, which is way different.  And believe it or not, not even all real numbers are alike.  Some can be represented as the ratio of two integers such as 2/3, and some cannot.  The ones that can are called rational and the ones that can’t are called irrational.  So, the next time someone you know starts talking about numbers, ask them what kind of number and see if they give you a funny look.