You don’t have to use/view Jupyter Notebook files to learn Python. A Jupyter Notebook is a way to combine code (not just Python) and commentary that can be shared and run by others who don’t know scripting (or the data processing content), but may want to see and understand the methods, processes, explanation, and results of scripted workflows.
Jupyter is an option for those interested in running Python scripts in an environment that has some additional commentary that often doesn’t exist with some Python scripts (especially those that don’t have any in-line comments). This section shows how to download and unzip the ArcPy_Bytes.zip file, then use Jupyter to open, view, and run one of the Jupyter files containing Python script within the Jupyter notebook.
RECOMMENDATION FOR JUPYTER NOTEBOOK FILES: The default location folder where Jupyter starts is the users folder on the C drive (e.g. C:\users\<user name>). Keep this in mind when downloading and extracting the files (the .ipynb, the .py, and the data folder/files). It is recommended that the user download the ArcPy_Bytes.zip (or any other file found on this site) to a folder/subfolder in the C:\users\<user name> folder before opening and running the Jupyter notebook files. If users want to change the default folder for Jupyter, see these instructions from ESRI.