Partial application and currying are a feature that is often mysterious to the uninitiated. Why do functional programmers care about such a seemingly useless thing? Partial application is an important part of the "FP toolkit" and we'll why and provide use cases for the importance of having partial application.
Simple made easy - https://www.infoq.com/presentations/Simple-Made-Easy
Scott Wlaschin https://fsharpforfunandprofit.com/fppatterns/
https://vimeo.com/113588389 - OO Patterns to FP Patterns talk
Lodash/fp - https://github.com/lodash/lodash/wiki/FP-Guide
Ramda - http://ramdajs.com/