Most common icons can be divided into Application icons, List icons and Note icons.
There are also several indications of different sizes and small icons in the UI, which are defined by the application.
Small list icons should be kept very simple and two dimensional. Application icons and note icons can be three dimensional and more detailed.
The metaphors are usually taken from everyday situations, mostly from the office environment. The metaphors should be globally relevant, not offensive or ambiguous (see also chapter 13).
In all icons, the light comes from the upper left-hand corner. The shadows are on the bottom right and behind the object. The viewing angle of the objects in icons is from the front top left or right (and in small list icons, directly from the front).