How do you take out a pop up drain in the bath tub???

this is the type of drain plug that does not come out, it is a fixture in the drain...How do you take out a pop up drain in the bath tub???
Here's you a diagram of a standard waste and overflow. It show you how it goes together. There are different kind but this probably what you have. Hope it helps.How do you take out a pop up drain in the bath tub???
stopper usually unscrews (needs pliers)
the stopper just unscrews (counter clockwise)......but im wondering why u wanna take it out to begin with

wrinkles