Python Program to Print Hello world

Let us try to execute Python “Hello World” programs in different modes of Python programming.

Interactive Mode Programming

Example

Invoking the interpreter without passing a script file as a parameter brings up the following prompt −

$ python
Python 2.4.3 (#1, Nov 11 2010, 13:34:43)
[GCC 4.1.2 20080704 (Red Hat 4.1.2-48)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>

Output

Type the following text at the Python prompt and press the Enter −

>>> print "Hello, Python!"

Example

If you are running new version of Python, then you would need to use print statement with parenthesis as in print ("Hello, Python!");. However in Python version 2.4.3, this produces the following result −

Hello, Python!

Script Mode Programming

Invoking the interpreter with a script parameter begins execution of the script and continues until the script is finished. When the script is finished, the interpreter is no longer active.

Example

Let us write a simple Python program in a script. Python files have extension .py. Type the following source code in a test.py file −

print "Hello, Python!"

We assume that you have Python interpreter set in PATH variable. Now, try to run this program as follows −

$ python test.py

Output

This produces the following result −

Hello, Python!

Example

Let us try another way to execute a Python script. Here is the modified test.py file −

#!/usr/bin/python
print "Hello, Python!"

We assume that you have Python interpreter available in /usr/bin directory. Now, try to run this program as follows −

$ chmod +x test.py # This is to make file executable
$./test.py

Output

This produces the following result −

Hello, Python!