In the new Mac OS X Lion operating system, there has been a noticeable change to the interface: the removal of the scrollbar. Users can adjust their settings to add scrollbars back in, but the fact that this option is even offered speaks volumes about the diminishing role of this once-indispensable interface element.

Since the early days of GUIs, the scrollbar has provided a way for users to navigate around an object that’s too large to fit within a window. However, over the past few years, users have been given other ways to scroll: mice with scrollwheels, laptop trackpads with scrolling capabilities, and a new set of gestures for mobile devices and tablets. With this reduction of the role of scrollbars, it’s important for designers to be conscious of the scrollbar’s benefits and drawbacks, and to know how to replace it with other elements that have similar benefits.

https://uxmag.com/articles/the-extinction-of-the-scrollbar