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 The idea of modular arithmetic was proposed by Carl Fredrick Gauss, a German mathematician called the "Prince of Mathematicians".
The process of wrapping around numbers when a certain value is attained is called
modular arithmetic.
The best example to explain the concept is the clock.

The clock shows the time for $$24$$ hours using only $$12$$ numbers, $$1$$, $$2$$, $$3$$,..., $$11$$ and $$12$$. After $$12$$, we use $$1$$ again for $$13$$ hours, $$2$$ for $$14$$ hours and so on. Here, the numbers are wrapped again from $$1$$ to $$12$$ to represent $$13$$ to $$24$$ hours. This way of again wrapping the numbers after a certain value is called modular arithmetic.
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Image source: https://commons.wikimedia.org/wiki/File:Carl_Friedrich_Gauss_1840_by_Jensen.jpg