Numeric data types in Python are used to store numeric values. Python has four defined numeric types: plain integers, long integers, floating values, and complex numbers.

The int type (plain integers) represents whole numbers that can be either positive or negative. The long type (long integers) are integers of infinite size. They're written as whole numbers (either positive or negative) followed by the character L, like 70L or 4891L. The float type (floating values) represents real numbers, but are often written in scientific notation or decimal points to divide the number into parts. The complex number type is represented by a formula: a + bJ. In the formula, a and b represent floating values, and J is always the square root of -1. The complex number type is not used often in Python.

To check which numeric type your value belongs to, use the isinstance method to check for plain, long, floating, and complex numeric types.