Caching (edit)
https://www.iozoom.com/different-types-of-data-caching/
https://www.clariontech.com/blog/how-caching-helps-in-improving-performance-of-the-application
http://tutorials.jenkov.com/software-architecture/caching-techniques.html
https://medium.com/system-design-blog/what-is-caching-1492abb92143