# What is the differena

## Main Question or Discussion Point

what is the differenae between natural and real numbers

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Real numbers (R) are "all" numbers, so all the fractions and all the other (irrational) numbers like $\sqrt{2}$ and $\pi$. If you want, you can think about a real number as any number which can be written in a (infinite, repeating or non-repeating) decimal expansion, like 1.23495012398530913298.......
(Sometimes, blackboard bold notation is used, for example $\mathbb{N}, \mathbb{R}$ instead of N, R.