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DECLARING AND INITIALISING A VARIABLE
KEYWORDS AND IDENTIFIERS
In Python, you can declare and initialise a variable in one step. For example:

In Python, keywords and identifiers are two important concepts that define the structure and x = 5
naming conventions of a program. y = 10
print("x =", x)
KEYWORDS
print("y =", y)
Keywords are reserved words with special In this example, the variables x and y are initialised with the values 5 and 10, respectively.
meanings in Python, used for tasks like control Python has 35 reserved keywords that cannot The output will be:
flow (if, for, while), functions (def) and classes be used as variable names.
(class). They cannot be used as variable x = 5
y = 10
names. Here is a list of Python keywords:
You can also assign the same value to multiple variables in a single line:
False None True and as assert
async await break class continue def a = b = 30
del elif else except finally for print("a =", a)
from global if import in is print("b =", b)
lambda nonlocal not or pass raise
In this case, both a and b will store the value 30 and the output will be:
return try while with yield
You cannot use keywords as variable names. For example, you cannot name a variable ‘if’ or ‘for’. a = 30
b = 30
IDENTIFIERS Additionally, you can assign multiple values to multiple variables in a single line. For example:

An identifier is a name used to uniquely identify a variable, function, class or object in Python. It
name, age, city = "John", 25, "London"
represents the values you store, like numbers or text.
print("Name:", name)
Examples of Identifiers: print("Age:", age)
print("City:", city)
Variable identifiers: age, score, temperature
The output will be:
Function identifiers: print_message(), calculate_sum()
Name: John
Class identifiers: Person, Student Age: 25

City: London
VARIABLES IN PYTHON

In Python, variables store values that can be accessed or changed later. Their names are DATA TYPES
identifiers and you don’t need to specify their type because Python is dynamically typed.
A data type defines the kind of value a variable can hold and the operations allowed on it.
RULES FOR NAMING VARIABLES For example, names are strings (text) and can be changed to uppercase or lowercase, while age,

When creating variable names, make sure to follow these rules: price and marks are numbers, either integers or floats and can be used in calculations.
Variable names can contain letters (a-z, A-Z), digits (0-9) and underscores (_). Let’s look at some commonly used data types in Python:

Variable names must begin with a letter or an underscore (_), but not a number. int: It represents positive or negative whole numbers (without fractions).
Variable names are case-sensitive, so ‘age’ and ‘Age’ are considered two different variables. For example:
a = 9
Variable names cannot use Python keywords (such as if, else, for) as variable names.
Variable names cannot contain spaces.

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