So today I read about the information that is imparted through design. Information used for a task is combination of internal knowledge and external knowledge. Internal knowledge is the knowledge in user’s mind and it is required to perform the task. While external knowledge is the information supplied by the design. Now the goal of any design is to make it easier for the user to perform a task. So if the designer provides more external knowledge, the user will have to rely less on its internal knowledge, this leads to less cognitive load.
I started thinking about scenarios or examples for the application of this concept. Icons came to my mind. I’ve done a research project where I was trying to understand the characteristics of an icon design, which makes them easily interpretable. One of the characteristics that came up in this study was: icon design should be abstract i.e., it shouldn’t have complex details. It should be made up of simple lines and arrows. It shouldn't contain intrinsic details in it. Now I understand the reason.
As designers we should provide the minimum amount of information; minimum information that is required for the user to distinguish between different icons. Using lines and arrows solves our purpose. They ensure low complexity thus low cognitive load for the user. Working with simple things like lines and arrows, makes it hard to design complex things. While at the same time, it can be different enough to be distinguishable from other icons.
Similar to this, is the concept of Affordances. Design elements should have correct affordances to it, so that the user gets a good amount of external knowledge about how to use the element. They should not require developing too much internal knowledge, i.e. learning things or processes. An example of this, is the iPhone toggle button. It is a solid circle and a cylindrical depressed space. This space provides the icon with the affordance. It imparts knowledge about sliding the circle. This icon uses “constraints” as well, to direct users towards the right action. Constraining from all other sides except the sliding direction helps guide users for the slide action, sliding it in the right direction.