Python if...else Statement

1. Basic if Statement

age = 20

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

Executes the block only when the condition evaluates to True.

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2. Using if...else Statement

temperature = 15

if temperature > 25:
    print("It's warm outside")
else:
    print("It's cold outside")

Provides an alternative execution path when the condition is False.

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3. Using if...elif...else Chain

score = 85

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

Allows testing multiple conditions in sequence.

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4. Nested if Statements

username = "admin"
password = "1234"

if username == "admin":
    if password == "1234":
        print("Access granted")
    else:
        print("Incorrect password")

An if block can exist inside another for complex logic.

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5. Using Logical Operators in Conditions

age = 25
is_verified = True

if age > 18 and is_verified:
    print("User can proceed")

Combine multiple conditions using and, or, and not.

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6. Short-Hand if Statement (Single Line)

x = 10

if x > 5: print("x is greater than 5")

Useful for minimal conditional checks.

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7. Short-Hand if...else (Ternary Expression)

num = 7

result = "Even" if num % 2 == 0 else "Odd"
print(result)  # Output: Odd

Compact inline conditional assignment.

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8. Checking Multiple Values with in

day = "Sunday"

if day in ["Saturday", "Sunday"]:
    print("Weekend")
else:
    print("Weekday")

Efficient alternative to chained OR conditions.

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9. Comparing Strings in Conditions

username = "Alice"

if username.lower() == "alice":
    print("Welcome Alice")

Common technique to handle case-insensitive comparisons.

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10. Using pass in if Statement

value = 5

if value > 0:
    pass  # Placeholder for future logic

print("Program continues...")

pass acts as a syntactic placeholder to avoid errors for empty blocks.