CONTROLLERS, single method or different methods for different actions?

It may still be present in some conventions, CI too denotes non-public methods that way for easier readability.

What I was explaining is that you don't actually need to use it and that he term "private" means a different thing.

well then what does 'private' mean? i am referring specifically to what is in the codeigniter 3 manual for how to prevent methods in a controller from being publicly available. is there something else that bears on this and if yes please explain or link to a source so we can understand what you are referring to.
https://codeigniter.com/user_guide/gener...te-methods