app.js// reads in sample data from a json file, adds values from relevant categories to objects, and then uses those objects in functions to build visualizations using the plotly.js library.

index.html// renders the visualizations, changing with optionChanged javascript function.

The dataset reveals that a small handful of microbial species (also called operational taxonomic units, or OTUs, in the study) were present in more than 70% of people, while the rest were relatively rare.