Editing Scroll wheel (section)

== Functionality ==
The scroll wheel is placed horizontally between the mouse buttons and commonly uses vertical scrolling, wherein rolling the wheel from the bottom side to the top is known as scrolling "upward" or "forward", while the reverse, i.e. rolling the wheel from the top side to the bottom, is known as scrolling "downward" or "backward".

In a [[graphical user interface]], the "upward" motion moves contents of the window downward (and the [[scrollbar]] thumb, if present, upward), and vice versa. In other configurations (sometimes called "natural scrolling") the effect is inverted.

On most mice, the scroll wheel can often also be used as a third, middle [[mouse button]] by pressing down on it,<ref>{{cite web|url=https://www.pcworld.com/article/515710/hasslefreepc-50.html|title=Bring Your Middle Mouse Button to Life|last=Broida|first=Rick|work=[[PC World]]|date=2009-12-22|access-date=2022-03-02|archive-url=https://web.archive.org/web/20230302034230/https://www.pcworld.com/article/515710/hasslefreepc-50.html|archive-date=2023-03-02|url-status=live}}</ref> known as the '''scroll button'''.{{anchor|Button}}

Some mice's scroll wheels can scroll horizontally by [[wikt:tilt|tilt]]ing them to the left or right,<ref>{{cite journal|title=Design and validation of virtually multiple mouse wheels|last1=Lee|first1=Kuo-Wei|last2=Lee|first2=Ying-Chu Lee|journal=International Journal of Industrial Ergonomics|publisher=[[Elsevier]]|date=July 2010|volume=40|issue=4|pages=392–401 |doi=10.1016/j.ergon.2010.03.004}}</ref> or there may be additional wheel on a perpendicular axis located elsewhere on the mouse.

The wheel is often, but not always, engineered with [[detent]]s to turn in discrete steps, rather than continuously as an analog axis, to allow the operator to more easily intuit how far they are scrolling.<ref>{{cite web|url=https://www.embedded.com/tear-down-high-end-mouse-goes-where-no-mouse-has-gone|title=Tear Down: High-end mouse goes where no mouse has gone|last=Nass|first=Richard|work=Embedded.com|date=2006-12-01|access-date=2023-03-02|archive-url=https://web.archive.org/web/20230302014535/https://www.embedded.com/tear-down-high-end-mouse-goes-where-no-mouse-has-gone/|archive-date=2023-03-02|url-status=live}}</ref><ref>{{cite web|url=https://www.pcgamer.com/do-you-like-your-mouse-wheel-to-click-when-you-scroll-or-spin-freely|title=Do you like your mouse wheel to click when you scroll, or spin freely?|last=Livingston|first=Christopher|work=[[PC Gamer]]|date=2020-03-12|access-date=2023-03-02|archive-url=https://web.archive.org/web/20230302015302/https://www.pcgamer.com/do-you-like-your-mouse-wheel-to-click-when-you-scroll-or-spin-freely|archive-date=2023-03-02|url-status=live}}</ref>

[[File:BlackBerry 7510, side-back view.jpg|100px|thumb|Trackwheel (1) on a [[BlackBerry]]]]

Scroll wheels are prevalent on modern computer mice and have become an integral part of the [[hardware interface]]. However, non-wheeled mice are still available.

Some user interfaces, like [[Cinnamon (desktop environment)]], allow using it to adjust '''brightness''' and '''volume''' by pointing at the respective taskbar icon while scrolling.