Smallest Two-Digit Number
The smallest two-digit number is 10. Let's break it down further to understand why 10 is the smallest two-digit number.

Definition of Two-Digit Number
A two-digit number is a number that has two digits, with the first digit being non-zero. In other words, the smallest two-digit number should have the smallest possible value for the tens place (the first digit) and the ones place (the second digit).

Explanation
- In a two-digit number, the tens place can have a value from 1 to 9, as it cannot be zero for it to be a two-digit number.
- The ones place can have a value from 0 to 9.
- To find the smallest two-digit number, we need to assign the smallest possible value to the tens place, which is 1, and the smallest value to the ones place, which is 0.
- Therefore, the smallest two-digit number is 10 (1 in the tens place and 0 in the ones place).

Conclusion
In conclusion, the smallest two-digit number is 10, with the tens place having the smallest possible value of 1 and the ones place having the smallest value of 0. This makes 10 the smallest two-digit number according to the rules of two-digit numbers.