Python: Hello World Program

Learn how to write a “Hello, World!” program in Python using multiple methods. Understand the basic syntax and different approaches to print “Hello, World!” on the screen. Perfect for beginners in Python programming.

Method 1: Using the print Function

The “Hello, World!” program is a classic introduction to programming. It is a simple program that outputs “Hello, World!” to the screen, demonstrating the basic syntax of the language and the use of the print function.

Algorithm:

Step 1: Start
Step 2: Input: No input required.
Step 3: Process:

        (i) Use the print function to output the string "Hello, World!"    
            to the screen.

Step 4: Output: "Hello, World!" is printed on the screen.
Step 5: Exit

Pseudocode:

function hello_world():
    print("Hello, World!")

Python Implementation:

def hello_world():
    print("Hello, World!")

# Example usage
hello_world()

Step-by-Step Explanation:

Function Definition (hello_world):

• Define a function hello_world with no parameters.

Print Statement (print(“Hello, World!”)):

• Use the print function to output the string “Hello, World!” to the screen.

Example Usage:

• Call the function hello_world() to execute the print statement and display “Hello, World!”.

Method 2: Using a Variable

Algorithm:

Step 1: Start
Step 2: Input: No input required.

Step 3: Process:
        (i) Assign the string "Hello, World!" to a variable.
        (ii) Use the print function to output the value of the variable.

Step 4: Output: "Hello, World!" is printed on the screen.
Step 5: Exit

Pseudocode:

function hello_world_variable():
    message = "Hello, World!"
    print(message)

Python Implementation:

def hello_world_variable():
    message = "Hello, World!"
    print(message)

# Example usage
hello_world_variable()

Step-by-Step Explanation:

Function Definition (hello_world_variable):

• Define a function hello_world_variable with no parameters.

Variable Assignment (message = “Hello, World!”):

• Assign the string “Hello, World!” to the variable message.

Print Statement (print(message)):

• Use the print function to output the value of the variable message to the screen.

Example Usage:

• Call the function hello_world_variable() to execute the print statement and display “Hello, World!”.

Method 3: Using String Formatting

Algorithm:

Step 1: Start
Step 2: Input: No input required.

Step 3: Process:
        (i) Use the print function with an f-string to output the string 
            "Hello, World!".

Step 4: Output: "Hello, World!" is printed on the screen.

Pseudocode:

function hello_world_format():
    print(f"Hello, World!")

Python Implementation:

def hello_world_format():
    print(f"Hello, World!")

# Example usage
hello_world_format()

Step-by-Step Explanation:

Function Definition (hello_world_format):

• Define a function hello_world_format with no parameters.

Print Statement (print(f”Hello, World!”)):

• Use the print function with an f-string to output “Hello, World!” to the screen.

Example Usage:

• Call the function hello_world_format() to execute the print statement and display “Hello, World!”.

Summary:

– Purpose: To demonstrate the basic syntax of Python by printing “Hello, World!” using different methods.

– Methods Covered:

• By using the print function directly.

• Using a variable to store the string and then printing it.

• Using string formatting with an f-string.

– Input: No input required.

– Output: “Hello, World!” is printed on the screen.

– Algorithm Efficiency: All methods have a time complexity of O(1), as they perform a simple print operation.

By learning these methods, beginners can understand the simplicity and flexibility of Python’s print functionality, providing a solid foundation for more complex programming tasks.