Python: 'Hello, World!' Program
In this tutorial, you will learn to write and run your first 'Hello, World!' program in Python.
We first start the Python Shell in both MacOS and Linux systems.
Python comes pre-installed on Mac OS X. However, it is most likely the older 2.x version. You can check its version with the command:
$ python --version
To start the interactive shell for the Python interpreter, type
python in the terminal and press
This interactive shell is known as Python Shell. The interpreter is in interactive mode when the prompt consists of three greater-than signs (
>>>), known as the Python REPL prompt.
Python 2.7.10 (default, Oct 6 2017, 22:29:07) [GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.31)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>>
If you have just typed that in your console and want to exit, type
Or if you have downloaded and installed the updated version Python 3.x, you can also just type
python3 in the terminal to start the updated shell.
The prompt is ready to accept Python commands.
Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 26 2018, 23:26:24) [Clang 6.0 (clang-600.0.57)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>>
We will make use of the Python function
print() to print our 'Hello, World!' message. Type
print('Hello, World!') and hit
print() function is passed the string value 'Hello, World!', which is also known as an argument (a value which is passed to a function is called an argument).
>>> print('Hello, World!')
print() function prints the string
Hello, World! to the console.
exit() to quit the shell.
As in Mac OS, you type
python3 in the terminal to start the Python Shell.
IDLE's Python Shell
Python's IDLE (Integrated DeveLopment Environment) is both code editor and interactive interpreter combined.
In Mac OS, get to
/Applications and expand the
/Python 3.x directory
Python's IDLE is launched. You will see the interactive Python prompt
print('Hello, World!') into the new unamed file.
Save the program with
.py extension inside some directory. Here, I have saved it as
hello.py inside the
To run our
hello.py script, go to
Run option and select
Run Module (F5).
It will print the "Hello, World!" statement into the console.
From the Command Line
Navigate to the
/python-programs directory where the
hello.py script file is located. Next run the below command.
$ python3 hello.py
- REPL is short for Read-Eval-Print-Loop.