If you feel like you’re missing an inside joke, here’s an explanation.
In object oriented languages, languages that don’t simply support object oriented programming but try to enforce their vision of it, you can’t pass around a simple function. You have to pass around an object that contains the function.
Functions are analogous to verbs and objects are analogous to nouns. In contrast to spoken English where the trend is to turn nouns into verbs, OOP wraps verbs up as nouns.
“Sometimes, the elegant implementation is a function. Not a method. Not a class. Not a framework. Just a function.” — John Carmack