Place value is the value of a digit based on its position in a number. In a whole number, each digit has a place value that is a power of 10. The place values start from the right and increase by powers of 10 as you move to the left. The first digit on the right is in the ones place, the second digit is in the tens place, the third digit is in the hundreds place, and so on.

For example, in the number 345, the digit 5 is in the ones place, the digit 4 is in the tens place, and the digit 3 is in the hundreds place. The place value of the digit 5 is 5 x 1 = 5, the place value of the digit 4 is 4 x 10 = 40, and the place value of the digit 3 is 3 x 100 = 300.

Understanding place value is important for performing operations such as addition, subtraction, multiplication, and division. It helps us to correctly identify the value of each digit and determine the overall value of a number.