Understanding if, if-else, and if-elif-else Statements in Python

What are if, if-else, and if-elif-else ?

These are Python’s tools for decision-making. They let your program choose between actions based on conditions you set. Think of them as decision checkpoints:

•  if :Executes a block of code only if a condition is true.
• if – else: Chooses between two actions—one for true and another for false.
• if – elif – else : Chooses between multiple actions by checking several conditions one by one.

Let’s learn one by one in detail with coding examples:

The ‘ if ‘ Statement

if statement evaluates a condition (a test, like comparing numbers). If the condition is true, the code inside the if block runs. Otherwise, it skips the block.

Example : Checking Age

age = 20
if age >= 18:
    print("You are eligible to vote!")        

Code Explanation: 

• The condition age > = 18 checks if the value of age is 18 or more.
• If it’s true, the message “You are eligible to vote!”   is printed.
• If the age were less than 18, nothing would happen.

Imagine you’re checking if you can enter a movie theater:

• If your age is 18 or older, you’re allowed in.
• Otherwise, you’ll just stand outside—but no one tells you explicitly why.

The ‘if-else’ Statement

What if you want your program to respond when a condition is not true? This is where if – else comes in. it gives your program an alternate option if condition is not true.

Example : Checking Age

age = 16
if age >= 18:
    print("You are eligible to vote!")
else:
    print("Sorry, you're too young to vote.")        

Explanation

• If the condition age > = 18 is true, the program prints the first message.
• Otherwise, it runs the else block, showing the second message.

Let’s go back to the movie theater example:

• If you’re 18 or older, you enter the theater.
• If you’re younger, the staff tells you, “Sorry, come back when you’re older.”

The if – elif – else Statement

Sometimes, you have multiple conditions to check. For this, Python provides the if – elif – else statement. Think of it as a series of checkpoints.

Example: Exam Grades

score = 85
if score >= 90:
    print("You got Grade A")
elif score >= 80:
    print("You got Grade B")
elif score >= 70:
    print("You got Grade C")
else:
    print("You need to work harder.")        

Code Explanation

• The program checks each condition in order.
• If score>=90 is true, it prints “You got Grade A”   and skips the rest.
• If not, it moves to the next condition score> = 80 and so on.
• If none of the conditions are true, the else block runs.

Think of this as choosing transportation based on how far you need to travel:

• If the distance is less than 1 km, you walk.
• If it’s between 1 and 10 km, you bike.
• If it’s more than 10 km, you drive.
• If there’s no way to travel, you stay home.

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