What is the largest $3$ digit number?

Hint: We know that there are infinite numbers and their counting is not possible because there are no limits to numbers. Basically in the number system we deal with different numbers and there are so many digits we start with one digit that is termed as one after it comes two digit numbers where we have tens and ones, then three digit numbers it comes as hundreds, tens, ones.
In this question we have to find out the largest three digit number.
so their place values will be hundred, tens, ones. To know the smallest three digit number we need to find the number which comes last in the $3$ digit terms.

Complete step-by-step answer:
We are asked to find the largest of three digit number
from $1$ to $9$ they are termed as one digit numbers.
from $10$ to $99$ they are termed as two digit numbers.
Let's discuss about three digit numbers , as it starts from 100 moving on it ends at 999.
So, $901-999$ is the highest line in three digit number and numbers.
$901,902,903,......,999$
We can clearly see that $999$ is the largest three digit number.
So we can conclude that smallest three digit number is $100$ and largest three digit number is $999.$
after $999$, there starts four digit numbers which is a thousand .

Note:
In the numeral system the place values start as ones, tens, hundreds, thousands, ten thousandths, lakhs then tan lakhs after that comes crores and then we reach to ten crores and more.
When it is asked to find out the smallest and largest any digit number you can simply answer using the digits $1$ and $9.$
Smallest digits will have $1$ as their first term and zeroes will be added accordingly and highest or largest will be $9$.
example- largest two digit number is $99$, it can be easily written as $9$ at one place and tens place.
Just remember the number of digits asked, just write $9$ that many times, it will save your time.
The smallest number is hundred while the largest number is $999$