Natural numbers:- The numbers 1 , 2 , 3 . . . which we use for counting are known as natural numbers.
Whole numbers:- If we add the number zero to the collection of natural numbers, we get whole numbers. Thus 0 , 1 , 2 , 3 . . . . form the collections of whole numbers.
Predecessor :- A number that comes before the given number. Eg: the predecessor of 12 is 11.
Successor:- A number that comes after a given number. Eg: the successor of 14 is 15.
Additive identity:- The number 0 is called additive identity.
Multiplicative identity :- The number 1 is called the multiplicative identity.