There are two types of numeric literals: exact and approximate.
An exact numeric literal is a numeric value without a decimal point, such as 65,– 233, and +12. Using the Java integer syntax, exact numeric literals support numbers in the range of a Java long.
An approximate numeric literal is a numeric value in scientific notation, such as 57.,– 85.7, and +2.1. Using the syntax of the Java floating-point literal, approximate numeric literals support numbers in the range of a Java double.