Syntax

variable name = value

Example 

x = 168
y = "Hello"

Rules for Python variables:
❶ Variable names "must" start with a letter or an underscore character.
❷ Variable names "cannot" start with a number.
❸ Variable names can only contain alpha (A-z) numbers (0-9) characters and underscores (_).
❹ Variable names are case sensitive (abc, Abc and ABC are three different variables).
❺ Variable names cannot be keywords.

Example

names   = "Python"
na_mes  = "Python"
_na_mes = "Python"
nAMES   = "Python"
NAMES   = "Python"
names1  = "Python"

Illegal variable names.

123x = "Python" ( X )
x-x  = "Python" ( X )
_x x = "Python" ( X )
for  = "Python" ( X )

myHouse

Pascal Case: Capitalize the first letter of each word.

MyHouse

Snake Case: The first letter of each word is lowercase and each space is underscored ( _ ).

my_house_name

Example

my_name = 'python'
print(my_name)

myName = 'Python'
print(myName)

Result

python
Python