Hello world script in python

Python Hello World Program

If you landed here, I am assuming you heard about Python programming and want to learn it. Well, that’s great. And the first step in learning any new programming language is to write the infamous Hello World program.

Let’s write our first Python program to print “Hello World” on the console. Let’s first get to the program and then we will learn how a Python program works. But, before that, we have to install Python on our computer.

Downloading and Installing Python

Python comes with different installers for different operating systems. So, the installation process also differs slightly, but it’s super easy and quick to install Python on any operating system.

1. Installing Python on Windows

Python provides a UI-based full installer for Windows. Go to the Python Releases for Windows page and from the “Stable Releases” section, download the Windows Installer EXE file. Just run the installer and it will install Python in Windows. Make sure to check the option to add Python binary folder to PATH to save you extra effort.

2. Installing Python on Mac OS

Go to the Python Releases for macOS page and from the “Stable Releases” section, download the macOS 64-bit universal2 installer package. Run the installer and it will be done in a jiffy.

3. Installing Python on Linux/Unix

Most of the Linux operating systems comes pre-installed with Python. Just run the “python3 –version” command to confirm it and check the version. If you want to use the latest version, follow the instructions on this page on Python Docs.

PyCharm IDE

If you are serious about learning Python, PyCharm IDE is a must. Go to the PyCharm Downloads page and download the free Community version for your operating system and install it. It’s super easy and it will save you a lot of time.

Python Hello World Program

Now that we have installed Python in our system, we are ready to write our Python program to print Hello World. Here is the python script to print “Hello World” on the console.

Yes, that’s it. It could not have been simpler than this.

Here is the output when this script is executed from the PyCharm IDE.

It’s the simplest program we will ever write. Let’s execute it from the python command line interpreter too.

$ cat hello_world.py print("Hello World") $ python3.7 hello_world.py Hello World $

Print “Hello World” from Python Command Line Interpreter

Python comes with an interpreter, which is a shell-like interface to run python scripts. Let’s see how to print the “Hello World” message on the console from the python interpreter.

$ python3.7 Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 16:52:21) [Clang 6.0 (clang-600.0.57)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> print("Hello World") Hello World >>>

Understanding Python Hello World Program

• The print() function is one of the built-in functions. This function prints the argument to the console.
• We are calling the print() function with the string argument “Hello World” so that it would get printed on the console.
• When we are executing a python script file, statements get executed one by one. The print() statement gets executed and it prints the “Hello World” message onto the console.

Summary

We started our journey to learn Python programming with the conventional “Hello World” program. We installed Python and PyCharm IDE in our system. We learned that the python program can be executed from the PyCharm IDE and terminal. We also got some idea about the python interpreter tool, which is very useful in running small python code snippets.

What’s next?

If you have reached this far, you are destined to learn Python. I would suggest you go through these 5 tutorials next.

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Первая программа на Python «Hello world»

В настоящее время используются только версия Python 3. Разработка и поддержка Python 2 прекращены, так что мы работаем с третей версией во всех статьях.

В какой-то момент ваших приключений в программировании вы, в конце концов, столкнетесь с Python 2. Не беспокойтесь. Есть несколько важных отличий, о которых вы можете почитать здесь.

Если вы используете Apple или Linux, у вас уже установлен Python 2.7 и 3.6+ (в зависимости от версии OS). Некоторые версии Windows идут в комплекте с Python, но вам также потребуется установить Python 3.

Он очень прост в установке на Linux. В терминале запустите:

$ sudo apt-get install python3 idle3

Это установит Python и IDLE для написания кода.

Для Windows и Apple я предлагаю вам обратиться к официальной документации, где вы найдете подробные инструкции: https://www.python.org/download

Запуск IDLE

IDLE означает «Интегрированная среда разработки». В вашей карьере программирования вы столкнетесь с многочисленными интегрированными средами разработки, хотя за пределами Python они называются IDE.

• Если у вас Windows, выберите IDLE из меню «Пуск».
• Для Mac OS, вы можете найти IDLE в приложениях > Python 3.
• Если у вас Linux, выберите IDLE из меню > Программирование > IDLE (используя Python 3.*).

Для Mac OS и Linux, в терминале, воспользуйтесь:

Когда вы впервые запускаете IDLE, вы видите примерно следующее на экране:

Это оболочка Python. А три стрелки называются шевронами.

Они означают приглашение интерпретатора, в который вы вводите команды.

Как написать “Hello, World!”

Классическая первая программа — «Hello, World!» . Давайте придерживаться традиции. Введите следующую команду и нажмите Enter:

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Hello World Programming Tutorial for Python

Estefania Cassingena Navone

🔹 Hello, World!

Hi! if you are reading this article, then you are probably starting to dive into the amazing world of programming and computer science. That’s great.

In this article, you will learn:

• How to write your first «Hello, World!» program in Python.
• How to save your code in a Python file.
• How to run your code.

Writing this program when you are starting to learn how to code is a tradition in the developer community.

Enjoy this moment because it will definitely be part of your memories in the coming months and years when you remember your first steps.

🔸 «Hello, World!» in the Python Shell

Step 1: Start IDLE

During this article, we will work with IDLE (Python’s Integrated Development and Learning Environment), which is automatically installed when you install Python. This is where you will write and run your Python code.

The first thing that you need to do is to open IDLE. You will immediately see the screen shown below.

This is called the Python shell (interactive interpreter). It is an interactive window where you can enter lines or blocks of code and run them immediately to see their effect and output.

💡 Tip: By default, you will see a smaller font size. You can customize this in «Options > Configure IDLE».

Step 2: Display the Message

You need to tell the program that you want to display a specific message by writing the appropriate line of code.

In Python, we use print() to do this:

• First, we write print .
• Then, within parentheses, we write the message or value that we want to display.

💡 Tip: The message «Hello, World!» is surrounded by double quotation marks because it is represented as a string , a data type that is used to represent sequences of characters in your code (for example, text).

Step 3: See the Output

You will see the following output if you write this line of code in the Python shell and press enter:

💡 Tip: You will notice that the color of the message inside print() changes to green when you add the last quotation mark.

This occurs because IDLE assigns different colors to the different types of elements that you can write in your code (notice that print is displayed in purple). This is called «syntax highlighting».

Great! You just wrote your first «Hello, World!» program in Python.

If you want to save it in order to run it later (or just to keep it as a nice memory of your first Python program!), you will need to create a Python file, so let’s see how you can do that.

🔹 «Hello, World!» in a Python File

Step 1: Create a File

To create a Python file in IDLE, you need to:

💡 Tips: You can also use the keyboard shortcut Ctrl + N .

After you click on New File , you will immediately see a new file where you can write your code:

Step 2: Write the Code

In the new file, write this line of code to print «Hello, World!» :

💡 Tip: The thick vertical black line shows where the cursor is currently at.

Step 3: Save the File

Save the new file by clicking on File > Save or by using the keyboard shortcut Ctrl + S . You will need to write a name for your file and choose where you want to save it.

After saving the file, you will see something very similar to this in the folder that you selected:

💡 Tips: By default, line numbers will not be displayed in the file. If you would like to display them (like in the images above) go to Options > Configure IDLE > General > Check the «Show line numbers in new windows» box.

Step 4: Run the Program

Now you can run your file by clicking on Run > Run Module:

A new window will be opened and you should see the output of your program in blue:

Now your program is safely stored in a Python file and you can run it whenever you need to.

🔸 Customize Your Program

You can customize your program to make it unique. You just need to edit the Python file and change the string.

For example, you can add your name after Hello, World! :

If you run the file, you will see the string displayed in the Python shell:

🔹 First Python Program Completed

Awesome work. You just wrote your first Python program.

Programming and Computer Science will be key for the future of humanity. By learning how to code, you can shape that future.

You’ll create amazing new products and platforms, and help take us one step further towards a world where technology will be part of every single aspect of our daily lives.

To learn more about the coding uses of Python, you might like to read my article «What is Python Used For? 10+ Coding Uses for the Python Programming Language»

I really hope that you liked my article and found it helpful. Follow me on Twitter @EstefaniaCassN and check out my online courses. ⭐️

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