A tooltip is more from an interaction. Hover over a button, and a tooltip pops up giving you a tip about the tool you are about to click.
Balloons don't come from interaction, and they point to something specific. Like an annotation or something.
Toasts are notifications. They can disappear after a while, or they might have to be manually dismissed.
A modal is a popup that prevents you interacting with other things.
A dialog is a popup that lets you interact with other things