**What are numbers?**

Numbers are mathematical objects used to count, measure and label. These objects are abstract concepts and they are represented by symbols. These symbols are called **numerals.**
**Number Digits **

There are many numerals developed by humans for the past years. The most common numeral that we are using today is called the *Hindu-Arabic numerals*. This numerals uses the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 to represent numbers. There are other numerals like the **Roman numerals**, **Greek numerals** and **Cuneiform numerals**

To form a number/s we combine one or more of the numerals. An example using Hindu-Arabic numerals are 2, 25, 856, 6658.

Number | Digit/s |
---|---|

4 | one Digit Number |

22 | Two digit number |

125 | Three digit number |

- we can create as many digit as possible.
- The higher the digit the larger the number. So 111 is greater than 99, 1252 is greater than 999.
- We cannot start a number with 0. Example 056 is just the same as 56 or 00056 = 56.

**What are whole Numbers?**

There are many classifications of numbers, a **whole number is just one of them**. These are numbers that starts from 0 up to the largest number possible (0, 1, 2, 3, ...). These numbers doen't include fractions or decimals.

**What is a Place Value?**

A **Place Value** is a numerical value of a digit in a number based on its position. In whole numers the place values are ones (units), tens, hundreds, thousands, ten thousands, hundred thousands, millions, ten millions, hundred millions, billions, ten billions and so on.

Placing the *place value* of a number starts from right to left from ones, tens and so on and the rightmost place value in a number has the smallest value.

Number | Digits Place Value | |||
---|---|---|---|---|

Thousands | Hundreds | Tens | Ones | |

3,015 | 3 | 0 | 1 | 5 |

Meaning | 3 x 1000: There are 3 thousands on this number | 0 x 100: There are no hundreds | 1 x 10 : There is just one 10 | 5 x 1 : There are five ones or units |

3, 105 = 3x1000 + 0 x 100 + 1 x 10 + 5 x 1 |