### Theory:

A system of numeration is a system for expressing numbers with the help of digits in a consistent manner.
There are two types of number system:
1. Indian numeral system (Hindu-Arabic number system)
2. International numeral system
What is the Indian numeral system?
This system was invented between the $$1st$$ and $$3rd$$ centuries by Indian mathematicians. The system was adopted in Arabic mathematics by the $$9th$$ century, and then it came to known as the Hindu-Arabic system. The system later spread to Europe. It is the most widely used system of numerals.

The place values of digits are Ones, Tens, Hundreds, Thousands, Ten Thousands, Lakhs, Ten Lakhs, Crores, and so on.
Example:
Consider the number $$61,85,09,372$$ the place values of each digit are:

$$2$$ – Ones
$$7$$ – Tens
$$3$$ – Hundreds
$$9$$ – Thousands
$$0$$ – Ten Thousands
$$5$$ – Lakhs
$$8$$ – Ten Lakhs
$$1$$ – Crores
$$6$$ – Ten Crores
Let us go through the Indian numeral system place value table:
Periods on Ones:
 Place value Hundreds Tens Ones Number $$100$$ $$10$$ $$1$$ Number of zeros $$2$$ $$1$$ $$0$$
Periods on Thousands:
 Place value Ten Thousands Thousands Number $$10000$$ $$1000$$ Number of zeros $$4$$ $$3$$
Periods on Lakhs:
 Place value Ten Lakhs Lakhs Number $$1000000$$ $$100000$$ Number of zeros $$6$$ $$5$$
Periods on Crores:
 Place value Ten Crore Crore Number $$100000000$$ $$10000000$$ Number of zeros $$8$$ $$7$$