Why are there different types of captions?
A- There are two types of captions: roll-up and pop-on. Roll-up captions are used almost exclusively for live reporting or events. The words appear one at a time at the end of the line, and when a line is filled, it rolls up to make room for a new line. Pop-on captions are the standard for pre-taped material. The entire caption appears, all at once, anywhere on the screen. When a pop-on caption appears, all captions previously on the screen are erased.
