Conditions in Python (if, elif, else & Boolean Conditions)

1. What are Conditions in Python?

• Conditions help a program make decisions.
• They allow Python to choose what action to take based on different situations.
• Conditions work by checking whether something is True or False.

Example questions a program may ask:

• Is the user old enough?
• Does the user have a ticket?
• Is the game over?

2. What is an if Statement?

• An if statement runs a block of code only if a condition is true.
• If the condition is false, Python skips that block.

Example:

if condition:
    # code runs here

• If the condition is True, the code inside runs.
• If the condition is False, the code does not run.

3. Using if, elif, and else

• Python checks conditions from top to bottom.
• Only one block runs — the first one that is true.

Keywords:

• if → checks the first condition
• elif → checks another condition if the previous one was false
• else → runs when all conditions are false

Example idea:

• Check age
• If age is small → child
• Else if age is medium → teenager
• Else → adult

4. Conditions with Numbers

• Python can compare numbers using comparison operators:
  • Greater than >
  • Less than <
  • Equal to ==

Example:

age = 18
if age >= 18:
    print("You are allowed")
else:
    print("You are not allowed")

Python checks the condition and decides which message to print.

5. What is a Boolean?

• A boolean is a data type that stores:
  • True
  • False
• Booleans are used for yes or no situations.

Examples of boolean questions:

• Do you have a ticket?
• Is the user logged in?
• Is the light on?
• Is the game over?

6. Conditions Using Boolean Values

• When using booleans, we do not need comparison operators.
• Python directly checks whether the value is True or False.

Example:

has_ticket = True
if has_ticket:
    print("You may enter, you have a ticket")
else:
    print("You need to buy a ticket")

Explanation:

• If has_ticket is True → first message prints
• If has_ticket is False → else message prints

7. Why Boolean Conditions Are Important

Boolean conditions are used in:

• Login systems
• Payment checks
• Games (game over / game running)
• Apps and websites
• Button clicks

They help programs react automatically based on situations.

8. How Python Thinks

• Python checks conditions step by step
• It runs code only when conditions match
• This allows programs to behave intelligently

Conditions help your program:

• Think
• Decide
• React

9. Summary of What Students Learned

• What conditions are
• How if statements work
• How if, elif, else make decisions
• How conditions work with numbers
• What booleans are
• How to use boolean variables in conditions

10. Task for Students

Create boolean variables such as:

• is_raining
• is_student
• game_over

Use if and else to:

• Print different messages
• Decide what action should happen

Example idea:

• If it is raining → print “Take an umbrella”
• Else → print “Enjoy the weather”