What is a callback function?

Question

What is a callback function?

Answer 1

Call After would be a better name than the stupid name, callback. When or if condition gets met within a function, call another function, the Call After function, the one received as argument.

Rather than hard-code an inner function within a function, one writes a function to accept an already-written Call After function as argument. The Call After might get called based on state changes detected by code in the function receiving the argument.