Attention, memory and perception
Skeuomorphism
Designing digital things to look like their physical counterparts, so people can apply what they already know about the real object.
A trash can for deleted files, a toggle that looks like a switch, a notebook with paper texture: each borrows understanding from the physical world.
It helped people learn early graphical interfaces and touchscreens. Today it works best in small doses, for controls whose physical meaning is still clear.
In practice
A camera app with a round shutter button, and a bookshelf of covers for a reading app's library.
Common mistake
Copying the limits of the physical object along with its look, like a calendar that can only show one month because paper calendars do.
Where it comes from
The word skeuomorph was coined by archaeologists in the late nineteenth century for objects that keep the look of older materials. It became a design term with early graphical interfaces and was moved away from by Apple's flatter iOS 7 in 2013.