could you please give me the modern definition of it?
It has many definitions. Like a natural number is defined as a particular set, and any set that can be put into one-to-one correspondence with that set is said to have that number of elements.
Natural number
a natural number is defined as a particular set, and any set that can be put into one-to-one correspondence with that set is said to have that number of elements.
what is parity of zero? It is the quality of an integer (zero) being even or odd. Zero has the parity of even. why is zero even? Because it shares all the properties that characterize even numbers. what is a number? A mathematical object used to count, measure, and label. when was it first used? The first known system with place value was the Mesopotamian base 60 system (c. 3400 BC). are there different types of them? Numbers can be classified into sets, called number systems, such as the natural numbers and the real numbers. please describe the first type to me? These contain numbers like 0,1,2,3,.... and the second type? They include all the measuring numbers. do you know what the origin of the first type is? The most primitive method of representing a natural number is to put down a mark for each object.
wiki:25655011
Natural number [SEP] Modern definitions
Later, two classes of such formal definitions were constructed; later still, they were shown to be equivalent in most practical applications. Set-theoretical definitions of natural numbers were initiated by Frege. He initially defined a natural number as the class of all sets that are in one-to-one correspondence with a particular set. However, this definition turned out to lead to paradoxes, including Russell's paradox. To avoid such paradoxes, the formalism was modified so that a natural number is defined as a particular set, and any set that can be put into one-to-one correspondence with that set is said to have that number of elements.