Here are the links for the resources mentioned in the last lecture:
https://plot.ly
Package to install:
install.packages('plotly')
Reference for gglotly() examples:
https://plot.ly/ggplot2/
Reference for full ggplotly example documentation:
http://ropensci.github.io/plotly-test-table/tables/0e3d5ca144d27d8416318824c1b6ec1421a51045/index.html
Enjoy and have fun! Throughout the rest of the course we will still use just ggplot2 by itself for data visualization, but feel free to convert those plots to interactive figures!