To view consecutive lines of data on the display screen. The term scroll means that once the screen is full, each new line appears at the edge of the screen and all other lines move over one position. For example, when you scroll down, each new line appears at the bottom of the screen and all the other lines move up one row, so that the top line disappears.
The term vertical scrolling refers to the ability to scroll up or down. Horizontal scrolling means that the image moves sideways.
In theory, the display should move smoothly, as if it were a piece of paper being moved up, down, or sideways. In practice, however, scrolling is not always so smooth.
The scrolling method of viewing documents does not recognize page boundaries. One advantage to scrolling, therefore, is that you can look at the end of one page and the beginning of the next page at the same time.
Another method of viewing data is called paging, whereby an entire page is displayed at once. Each subsequent page replaces the previous page on the screen.