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Welcome to Python: Why This Language and How to Start
Step into the world of Python and see why it remains one of the most popular first programming languages in 2026, powering everything from tiny scripts to AI systems. You’ll get a clear picture of what you can realistically achieve in your first weeks and how this course will guide you there without overwhelm.
Welcome: What You Will Get From Python
Why Python, Why Now
Python is one of the most popular first programming languages in 2026. It is used by beginners, professional developers, scientists, and AI researchers.
Your Goals
In this short module, you will see what Python is used for, why we use Python 3, how Python runs your code, and where you can actually type and run Python yourself.
No Experience Needed
You do not need any previous coding experience. We will keep the language simple and focus on clear, practical steps so you can explain Python in your own words.
What Is Python, In Simple Words?
Python = Instructions
Python is a programming language: a special kind of language humans use to give step-by-step instructions to computers.
How To Think Of It
Think of Python as both a way to tell the computer what to do and a set of rules for writing instructions the computer can understand.
Why People Like Python
Python is readable, beginner-friendly, and powerful. The same language you start with is used in serious real-world projects.
What Is Python Used For in 2026?
Python Is Everywhere
In 2026, Python is used in web development, data science and AI, automation, games, and education. It is part of many tools you use every day.
Popular Use Cases
People use Python to build websites, analyze data, train AI models, write scripts to automate boring tasks, and make simple games.
Realistic First-Week Goals
In your first weeks, you can write small scripts, do calculations, ask the user questions, and automate tiny tasks. Big AI systems come later.
Check: Where Is Python Used?
Test your understanding of common Python use cases.
Which of these is a realistic use of Python in 2026 for many developers?
- Designing computer chips with a pencil and paper only
- Building web apps, data tools, and automation scripts
- Replacing all operating systems with a single Python file
Show Answer
Answer: B) Building web apps, data tools, and automation scripts
Python is widely used to build web apps, data tools, and automation scripts. It does not directly replace operating systems, and chip design involves much more than just Python.
Python 2 vs Python 3: What Matters for You
Python 2 Is Old
Python 2 reached end-of-life in January 2020. It no longer gets security updates, and new libraries focus on Python 3.
Python 3 Is Standard
Python 3 is the current standard. In early 2026, many people use versions like 3.11 or 3.12. Always choose the latest Python 3 from python.org.
What You Should Do
As a beginner, always use Python 3. If you see Python 2 in a tutorial, look for a Python 3 version. This course uses Python 3 for all examples.
Your First Python 3 Lines
Here is a tiny taste of Python 3 code. You do not need to understand everything yet. Just notice how readable it looks.
```python
This is a comment: Python ignores this line
1. Print a message
print("Hello, Python!")
2. Do a small calculation
result = 5 + 3
print("5 + 3 =", result)
3. Ask the user a question
name = input("What is your name? ")
print("Nice to meet you,", name)
```
What happens here:
- `print(...)` shows text on the screen.
- `result = 5 + 3` tells Python to add 5 and 3 and store the answer in `result`.
- `input(...)` asks the user to type something and press Enter.
You will write and run code like this very soon.
How Python Runs Your Code: The Interpreter
Meet the Interpreter
To run Python code, you use the Python interpreter. It is a program that reads your code and makes the computer follow your instructions.
Step-by-Step Process
You write code. The interpreter reads it line by line, translates it into lower-level operations, then executes those operations and shows results.
Two Ways to Use It
Script mode runs code from .py files like `python my_script.py`. Interactive mode lets you type one line at a time and see instant results.
Thought Exercise: Interpreter vs Human Reader
Imagine you are the Python interpreter.
You receive this list of instructions:
- Take a number.
- Add 10.
- If the result is greater than 20, say "Big!".
- Otherwise, say "Small or medium".
Now do this in your head for these starting numbers:
- 5
- 15
- 30
Questions to think about:
- What would you say for each starting number?
- How is this similar to what the Python interpreter does with code?
- Why is it important that instructions are clear and in the right order?
You do not need to write code yet. Just practice thinking like an interpreter: follow each step exactly, in order.
Where Can You Run Python? Local and Online
Local Setup
On your own computer, go to https://www.python.org, click Downloads, and install the latest Python 3. On Windows, check "Add Python to PATH" if you see it.
Online Options
If you cannot install Python, use online tools. Replit lets you create Python projects in your browser. Google Colab is great for notebooks and data.
Pick Your Tools
For this course, choose at least one local option and one online environment so you can practice Python in both places.
Tools: Editors, IDEs, and Notebooks
Simple Tools
IDLE comes with Python and is fine for your first steps. VS Code is a popular free editor; add the Python extension to make coding easier.
More Powerful Tools
PyCharm Community Edition is a full Python IDE for bigger projects. Jupyter and Google Colab notebooks mix code, text, and charts.
What You Need Now
In your first weeks, IDLE, VS Code with the Python extension, or an online notebook like Google Colab is more than enough.
Check: Running Python
Test your understanding of how to start using Python.
Which combination correctly matches a local setup and an online setup for running Python?
- Local: Google Colab, Online: VS Code
- Local: Python from python.org + IDLE, Online: Replit
- Local: Web browser only, Online: Your file system
Show Answer
Answer: B) Local: Python from python.org + IDLE, Online: Replit
Python from python.org plus IDLE is a local setup. Replit is an online environment. Google Colab is online, and VS Code is a local editor.
Key Terms Review
Flip these cards (mentally or on paper) to review the core ideas from this module.
- Python (as a language)
- A programming language used to give instructions to computers. Known for being readable, beginner-friendly, and powerful.
- Python 3
- The current standard version of Python. Actively maintained and recommended for all new projects and for learning.
- Python 2 end-of-life
- Python 2 stopped receiving updates in January 2020. New learners should not use it and should choose Python 3 instead.
- Interpreter
- A program that reads your Python code line by line, translates it into lower-level operations, and executes it.
- Script mode
- Running Python code saved in a .py file, for example using a command like `python my_script.py`.
- Interactive mode
- Typing Python commands one line at a time (for example in a Python shell or notebook) and seeing results immediately.
- Local setup
- Running Python on your own computer, for example by installing it from python.org and using IDLE or VS Code.
- Online environment
- Running Python in a web browser using services like Replit or Google Colab, without installing Python on your computer.
Key Terms
- IDE
- Short for Integrated Development Environment, a tool that combines an editor, debugger, and other features to help you write code.
- Python
- A popular programming language used for web development, data science, AI, automation, and more.
- Notebook
- An environment (like Jupyter or Google Colab) where you can mix code, text, and outputs in one document.
- Python 2
- An older version of Python that reached end-of-life in January 2020 and is no longer maintained.
- Python 3
- The modern, supported version of Python. Recommended for all new learners and projects.
- Interpreter
- A program that reads and executes code directly, line by line, instead of compiling it into a separate file first.
- Local setup
- Installing and running Python directly on your own computer.
- Script mode
- Running Python code from a saved .py file, usually using a command like `python file_name.py`.
- Interactive mode
- Running Python one command at a time in a shell or notebook and seeing immediate output.
- Online environment
- Running Python through a website in your browser, without installing it locally.