To check NaN value in Python, Use math.isnan() method or np.isnan() function or pd.isna() method or compare variable's value to the NaN value.

NaN stands for Not A Number which is a floating-point value that represents missing data. People always confuse between None and NaN because it looks similar, but both are quite different.

The None is a data its own(NoneType) used to define a null value or no value at all. None is not the same as 0, False, or an empty string. While missing values are NaN in numerical arrays, they are None in object arrays.

#python