Waffleplots, also called square pie charts - are very useful in communicating parts of a whole for categorical quantities.
Some useful links from where I learnt all this:
- https://paulvanderlaken.com/2019/01/25/visualization-innovation-waffleplots-and-swarmplots-aka-beeplots/
- http://edgar-treischl.de/2018/03/11/waffle-charts/
- Various github and stackoverflow articles and repositiories