I am unsure about the following so I would like to verify if my statements are true:
We can remove at most a single character ($Z\in\Gamma$) from the PDA (top ?) of the stack with one step of the PDA [I do not know what is the correct terminology]
We can add a string of characters $(\alpha\in\Gamma^{*})$ to the (top ?) of the stack with one step with one step of the PDA
I would also appreciate the help with the terminology I lack (that is, should I write top or bottom and how does a single step by the PDA called)