A decimal number can be defined as a number whose whole number part and the fractional part is separated by a decimal point.

The dot in a decimal number is called a decimal point.

Explanation: For example, \$64.5\$.
Here, \$64\$ and \$5\$ are separated by a point. So, \$64.5\$ is a decimal number.

Decimals that have the same number of digits to the right of the decimal point are referred to as like decimals..

Explanation: Let us discuss like decimals.
Decimals with the same number of decimal places are called like decimals.

For example, \$71.6\$ and \$62.3\$, in \$71.6\$ and \$62.3\$, there is only one decimal place after the decimal point, so \$71.6\$ and \$62.3\$ are like decimals.