1. Virtual Environment (venv)

1.1 A virtual environment is a self-contained Python environment:

• Has its own Python interpreter.
• Has its own site-packages folder (where libraries are installed).
• Is isolated from your system Python or other projects.
• Lets you use different library versions per project without conflicts.

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1.2 Using virtual environments is important because:

• It prevents package version conflicts between projects.
• Makes projects more portable and reproducible.
• Keeps your system Python installation clean.
• Allows testing with different Python versions.

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1.3 How to create and use one

# Create a virtual environment named 'myfirstproject'
C:\Users\Your Name> python -m venv myfirstproject

# --------------------------------------------------------------------------------------------

# Activate it (Linux/macOS)
$ source myfirstproject/bin/activate


# Activate it (Windows)
C:\Users\Your Name> myfirstproject\Scripts\activate


# Result: (The command line will look like this when the virtual environment is active)
(myfirstproject) C:\Users\Your Name>


# --------------------------------------------------------------------------------------------


# Install packages inside the virtual environment
C:\Users\Your Name> pip install requests


# --------------------------------------------------------------------------------------------


# Deactivate when done
C:\Users\Your Name> deactivate

# --------------------------------------------------------------------------------------------


# Delete Virtual Environment (Windows)
C:\Users\Your Name> rmdir /s /q myfirstproject


# Delete Virtual Environment (Linux/macOS)
$ rm -rf myfirstproject