Python Virtual Environment
I have been using PyCharm for awhile and never really thought about having to contain my Python environments (sense it does it for you), but every once in awhile I need to work on a different IDE or a team member and I start scrambling for directions online.
The main reason why you would want to create a virtual environment is to limit your installed Python modules to your project.
Quick Ref: https://docs.python.org/3/library/venv.html
Creating virtual environments
python3 -m venv /path/to/new/virtual/environment
Activating a virtual environment
source env/bin/activate
You can confirm your virtual environment by typing the following
which python
.../env/bin/python # you should see this
Leaving the virtual environment
deactivate