Conditional Statements in Python

Conditional statements are one of the most important building blocks in Python programming. They allow your program to make decisions based on conditions, just like we do in real life.

For example:

• If it’s raining → take an umbrella
• If marks ≥ 40 → pass
• If age ≥ 18 → eligible to vote

In Python, we use conditional statements to implement this logic.

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What Are Conditional Statements?

Conditional statements help the program execute different blocks of code depending on whether a condition is True or False.

Python supports the following conditional statements:

• if
• if else
• if elif else
• Nested if
• Shorthand if (ternary operator)

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if Statement in Python

The if statement executes a block of code only if the condition is True.

Syntax

if condition:
    # code executes if condition is True

Example

age = 20

if age >= 18:
    print("You are eligible to vote")

Output

You are eligible to vote

👉 If the condition is False, nothing happens.

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if else Statement

The if else statement executes one block if the condition is True and another block if it is False.

Syntax

if condition:
    # True block
else:
    # False block

Example

marks = 35

if marks >= 40:
    print("You passed the exam")
else:
    print("You failed the exam")

Output

You failed the exam

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if elif else Statement

When you have multiple conditions, use elif (else if).

Syntax

if condition1:
    # block 1
elif condition2:
    # block 2
else:
    # default block

Example

score = 85

if score >= 90:
    print("Grade A")
elif score >= 75:
    print("Grade B")
elif score >= 60:
    print("Grade C")
else:
    print("Fail")

Output

Grade B

👉 Python checks conditions from top to bottom and stops when it finds a True condition.

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Nested if Statements

An if statement inside another if is called nested if.

Example

age = 22
has_id = True

if age >= 18:
    if has_id:
        print("Entry allowed")
    else:
        print("ID required")
else:
    print("Underage")

Output

Entry allowed

👉 Use nested if carefully to keep code readable.

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Shorthand if (Ternary Operator)

Python allows writing simple if else in one line.

Syntax

result_if_true if condition else result_if_false

Example

a = 10
b = 20

print("A is greater") if a > b else print("B is greater")

Output

B is greater

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Comparison Operators Used in Conditions

Operator	Meaning
==	Equal to
!=	Not equal
>	Greater than
<	Less than
>=	Greater than or equal
<=	Less than or equal

Example

x = 5
print(x > 3)    # True
print(x == 10)  # False

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Logical Operators in Conditional Statements

Operator	Description
and	True if both conditions are True
or	True if any one condition is True
not	Reverses the condition

Example

age = 25
citizen = True

if age >= 18 and citizen:
    print("Eligible to vote")

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Common Mistakes Beginners Make

1. Forgetting colon : after condition
2. Using = instead of ==
3. Incorrect indentation
4. Writing unnecessary nested if

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Real-Life Use Cases of Conditional Statements

• Login authentication
• Checking eligibility (age, marks, experience)
• Validating user input
• Decision-making in games and apps
• Form validations

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Happy Learning !

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