When downloading a Jupyter Notebook file, the expectation is typically to receive a single file with the “.ipynb” extension. However, in certain circumstances, the download manifests as a folder instead. This occurs when the notebook contains elements referenced through relative paths, such as images, data files, or custom modules that reside in the same directory or subdirectories as the notebook. The browser, recognizing these dependencies, packages the notebook and its related assets into a single folder for a complete and self-contained download. An example would be a notebook using a logo.png file located in a ‘images’ subdirectory; downloading the notebook results in a folder containing the .ipynb file and the ‘images’ directory.
The phenomenon ensures that all necessary components for proper notebook execution are preserved and readily accessible to the user. This is crucial for reproducibility and portability, as it avoids broken links and dependencies that would otherwise arise if the notebook was downloaded in isolation. Historically, this behavior reflects the evolution of web browsers to better handle complex file structures and dependencies associated with web applications, including those generated by data science tools. This approach prioritizes the user experience by maintaining the integrity of the notebook’s intended functionality upon download.
