python How to Start with Python: A Beginner's Guide

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Python is one of the most widely used programming languages in the world. According to the Stack Overflow Developer Survey, Python ranked as the second most wanted language and the second most commonly used language among developers learning to code. 

Whether you want to build a website, a game, a chatbot, or a neural network, Python has something for you. In this guide, you will learn how to start with Python, from setting up your environment to writing your first program. You will also learn some basic concepts to help you become a confident Python programmer.

If you already know Python basics, look into our advanced Python Certification Course. It has practice quizzes and mock exams to help you prepare for the Python certification exam. 

Why Python?

Below are some of the features and benefits of Python that make it stand out from other languages.

Simplicity and Readability

One of the main advantages of Python is its simplicity and readability. Python has a clear and concise syntax that follows the English language and uses indentation to define blocks of code. This makes Python code easy to read and understand, not only for yourself but also for others who may review or collaborate on your code.

Below is a simple program that demonstrates Python’s simplicity and readability:

print("Hello, World!")

And here is how you can write the same program in Java:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

As you can see, Python code is much shorter and simpler than Java code. You don't have to worry about complex curly braces, semicolons, or things like that. You just have to write the print function and the message you want to print.

Python also has a lot of built-in functions and modules that can help you perform common tasks and operations without having to write a lot of code. For example, you can use the math module to access mathematical functions and constants, such as pi, sin, cos, sqrt, etc. You can also use the random module to generate random numbers, choices, or samples. 

Let’s look at how to use the `random` function. First, you have to import the function you want to use: 

import random

And then you can use them in your code, as shown below:

# Pick a random number between 1 and 10
number = random.randint(1, 10)
print(number)

# Shuffle a list of names
names = ["Alice", "Bob", "Charlie", "David", "Eve"]
random.shuffle(names)
print(names)

Powerful and Versatile

Another advantage of Python is its power and versatility. Python is a high-level, interpreted, and general-purpose language that can run on platforms such as Windows, Mac OS, Linux, etc. You can also use Python for various purposes and domains, such as web development, data analysis, machine learning, automation, and more.

It has a rich set of libraries and frameworks that provide many functionalities and tools for different applications. Some of the most popular and useful libraries and frameworks for Python include:

• Web Development: You can use Python to create dynamic and interactive websites and web applications. Some of the libraries and frameworks that can help you with web development are Flask, Django, Pyramid, etc. These frameworks allow you to handle requests, responses, sessions, cookies, templates, databases, etc., with ease and efficiency.
• Data Analysis: You can also use Python to analyze, manipulate, and visualize data from various sources and formats. Some of the libraries and frameworks that can help you with data analysis are Pandas, NumPy, SciPy, Matplotlib, Seaborn, etc. These libraries allow you to work with data structures, perform mathematical operations, and create plots, charts, graphs, etc. to display your data and findings.
• Machine Learning: Some of the libraries and frameworks that can help you with machine learning in Python are Scikit-learn, TensorFlow, PyTorch, Keras, etc. These libraries allow you to implement various machine-learning algorithms, such as classification, regression, clustering, etc. You can also use these libraries to implement neural networks and deep learning techniques, such as convolutional neural networks, recurrent neural networks, etc. 
• Automation: You can use Python to automate tasks and processes that are repetitive and time-consuming. Some of the libraries and frameworks that can help you with automation are Selenium, PyAutoGUI, Requests, Beautiful Soup, etc. These libraries allow you to control your web browser, send and receive HTTP requests and responses, and scrape web pages, with ease and speed.

These are just some of the examples of what you can do with Python. There are many more libraries and frameworks that can help you with other applications, such as game development, natural language processing, computer vision, etc. You can find and install these libraries and frameworks using the pip package manager, which is a tool that comes with Python. 

You can use the pip command in your terminal or command prompt to install, update, or uninstall packages, as shown below:

# Install the Flask package
pip install Flask

# Update the Flask package
pip install --upgrade Flask

# Uninstall the Flask package
pip uninstall Flask

Massive Community Support

The last, but not the least, advantage of Python is its massive community support. Python has a large and active community of developers and enthusiasts who contribute to its development and improvement. You can find a lot of resources, tutorials, courses, books, blogs, podcasts, and forums that can help you learn and improve your Python skills. 

You can also join online platforms, such as Stack Overflow, Reddit, or Discord, where you can ask questions, share your projects, and get feedback from other Python users. According to Statista, Python has the second-largest community, with about 15.7 million users worldwide. 

Communities make learning easier, fun, collaborative, and rewarding. It allows you to find learning materials, tips, mentors, and solutions when you get stuck.

Prerequisites

All you need for this tutorial is a computer with an internet connection. That’s because Python works on Windows, MacOS, and Linux. We'll guide you through downloading and installing Python, so no other software is required. Let's get started!

How to Set Up Your Python Environment

To start with Python, you need to install it on your computer and choose an editor or an IDE to write your code. In this section, you will learn how to do that.

Downloading and Installing Python

To download and install Python on your computer, visit the official Python download page. There, you will find different versions of Python available for different operating systems, such as Windows, Mac OS, Linux, etc. For this guide, we will use Python 3, the latest version of Python.

You can choose the version that matches your operating system and click on the download link. This will download an installer file, run this file, and follow the steps on the screen to install Python.

Make sure you check the option to add Python to your PATH, which will allow you to run Python from any directory. You can also customize the installation by choosing the features and components you want to install, such as the IDLE editor, the pip package manager, and the documentation.

After the installation is complete, you can verify that Python is working by opening a terminal and running the command below:

python --version

This should display the version of Python you have installed, as shown below:

If you see an error message or a different output, you may need to check your installation or your PATH settings.

Checking Your Python Version

It is important to know which version of Python you are using, as there may be some differences and incompatibilities between different versions. For example, Python 2 and Python 3 have some significant differences in syntax and features, such as the print function, the input function, the division operator, etc. Therefore, you need to make sure that you are using the same version of Python as the one you are learning from or the one that your code is written for.

If you want to get more information about your Python version, such as the build number, the date, and the compiler, you can use the -V or --version flag twice, as shown below:

python --version --version

This will display an output similar to this: 

Choosing an Editor or IDE

To write Python code, you need a text editor or an integrated development environment (IDE). Text editors,  such as Notepad, Sublime Text, or Visual Studio Code, allow you to create and edit plain text files. IDEs, such as IDLE, PyCharm, or Spyder, provide features and tools to help you write, run, and debug your code.

For this guide, we will use IDLE; to launch it, you can search for it in your Start menu or Applications folder. Launching it will open a window called the Python Shell, which is an interactive console where you can type and execute Python commands. You can use the Shell to test your code and experiment with different Python features.

To write a program, you need to create a new file by clicking on File -> New File, or pressing Ctrl+N. This will open a window called the Python Editor, where you can type and save your code. You can also open an existing file by clicking on File -> Open, or pressing Ctrl+O.

Writing Your First Program

The first program that most programmers like myself write is "Hello, World!", which simply prints a message on the screen. To write this program in Python, you only need one line of code:

print("Hello, World!")

The print function is a built-in function that takes an argument and displays it on the screen. The argument can be a string, which is a sequence of characters enclosed in quotation marks, such as "Hello, World!", or a number, such as 42, or a variable, which is a name that refers to a value, such as x in this expression “x = 10”

Before running your program, save it by clicking on File -> Save, or pressing Ctrl+S. You can give your file any name you want, but make sure it ends with the .py extension, which indicates that it is a Python file. For example, you can name your file hello.py.

After saving your file, you can run it by clicking on Run -> Run Module or pressing F5. This will execute your code and display the output in the Python Shell window. You should see something like this:

Hello, World!

Congratulations, you have just written and run your first Python program!

Don't stop here - keep challenging yourself by working on new projects that interest you. Try tweaking your "Hello World" program in different ways or build something simple, for instance, a calculator.

If you're up for another quick challenge, consider following our guide on how to Create A Simple Python Web Application That Interacts With Your Kubernetes Cluster.

Understanding Basic Syntax

Now that you have written your first program, let's take a closer look at the basic syntax and rules of Python. Syntax is the set of rules that defines how a language is written and structured. By following the syntax, you can write valid and meaningful code that can be understood by the computer and other programmers.

Some of the basic syntax rules of Python are:

• Indentation: Python uses indentation to define blocks of code that belong together. In Python, you need to indent your code by four spaces for each level of nesting. For example, if you have a function inside a loop, you need to indent the function by eight spaces. Indentation is very important in Python, as it affects the meaning and execution of your code. If you don't indent your code properly, you will get an IndentationError. 
• Comments: Comments are lines of text that are ignored by the computer and are used to explain your code. Comments can help you and other programmers understand what your code does and why. In Python, you can write comments by starting a line with the # symbol; this marks the rest of the line as a comment. See the example below:

# This is a comment

You can also write multi-line comments using triple quotation marks, which enclose a text block as a comment. See the example below:

"""
This is a multi-line comment
You can write as many lines as you want
"""

• Statements: Statements are the basic units of code that perform an action or a task. In Python, you can write statements on a single line or on multiple lines. See the example below:

x = 10; y = 20

Or, you can write a statement like this:

x = 10 
y = 20 

• Expressions: Expressions are the parts of code that produce or evaluate a value. In Python, you can write expressions using literals, variables, operators, functions, etc. The following are examples of expressions in Python. 

10

10 + 20

math.sqrt(x)

print(x)

These are some of the basic syntax rules of Python that you need to know and follow. By understanding and applying these rules, you can write valid and meaningful code that can be executed by the computer and understood by other programmers.

If you'd like to build an even stronger foundation in Python syntax and core concepts, I recommend checking out our interactive Python Basics course. In it, you'll find dozens of bite-sized lessons that help cement your understanding of data types, functions, object-oriented programming, and more.

Also, check out this article on How to Get Python Certification: The Step-By-Step Guide.

Conclusion

In this article, you have learned how to get started with Python, from installing it on your computer to writing your first program. You have also learned some basic concepts and terms. This is your first step towards becoming a Python programmer.

With the basics under your belt, you're now ready to start building more complex programs. Let me know in the comments if you have any questions. 

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