The scroll wheel that is located in the middle of the mouse is used to scroll up and down on any page without using the vertical scroll bar on the right hand side of a document or webpage. The scroll wheel can also be used as a third button on the mouse.

What is the use of scroll button?

The scroll wheel typically sits between the left and right buttons on the top of a mouse. It is raised slightly, which allows the user to easily drag the wheel up or down using the index finger. Pulling the scroll wheel towards you scrolls down the window, while pushing it away scrolls up.

How does the scroll wheel work?

The scroll wheel at the front of the mouse is mounted on a switch mechanism that detects both how much it's rotated and whether you've pressed it (it functions like the central button of a conventional mouse). Rotations of the scroll wheel can be detected in a variety of different ways.