In Python, variables are defined with certain rules. Let's get started reading about them!! Don't create variable with a number Eg: '12a'; #is wrong. Don't define any variables with space, instead we can define with intend mark. Eg: new word = Hello ; #is wrong new_word = Hello ; #is correct Don't create any variable contain any of these symbols: :'",<>/?|\!@#%^&*~-+ it's considered best practice ( PEP8 ) that names are lowercase with underscores avoid using Python built-in keywords built-in keywords like list and str avoid using the single characters l (lowercase letter el), O (uppercase letter oh) and I (uppercase letter eye) as they can be confused with 1 and 0