add more drop down menus by button

not really sure what the function is called, seen it on a site but lost the link.

looking to find out how to create it so that you can press a button, lets say add_dropdown and when you do it will add a drop down box to the page, but you can press the button X ammount of times and it will keep adding more dropdown boxes for ever click to the button.

i hope that made sense

There are several solutions for this. Do a search in google and you will find many of them.