# Number System - Natural Numbers (cardinal and ordinal numbers) -

A natural number $\mathbb{N}$ can be used for two purposes:

• to count (ie describe the size of a set)
• to order (ie or to describe the position of an element in a sequence).
0, 1, 2, 3, 4, ... or 1, 2, 3, 4,



The natural numbers are those used for:

Operation Example Words
counting there are six coins on the table cardinal numbers
ranking this is the third largest city in the country ordinal numbers

## Number systems

N is a number system.

where:

## Representation

### Symbol

In the base 10 numeral system, the symbols for natural numbers are written using ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.

### Class

In set theory, natural numbers can be represented by classes of equivalent sets. For instance, the number 3 can be represented as the class of all sets that have exactly three elements.

## Documentation / Reference

Recommended Pages Function - count (size of|length)

Counting occurs with cardinal numbers. Counting is a way to describe the size of a collection. Ie Number - Field

A field is a collection of “numbers” with the operator: +, -, , / Different fields are like different classes obeying to the same interface. Same as ?? A field is also known as abody: corps...
Number System (Classification|Type)

Numbers are classified according to how they are represented or according to the properties that they have. They have what's called a type. For systems for expressing numbers, see Numeral system. ...
Number System - Ordinal Number (Magnitude)

An ordinal number, or ordinal, is a natural number used for ordering. Ordering with numbers is also called ordering by magnitude. In set theory (Mathematics), an ordinal number, or just ordinal, is the... Ordinal Data

Ordinal data are data that can be ordered on an ordinal scale in order to rank them. Each ordinal data can therefore be translated into a number . This is a functionality/behavior of the data type... 