-  Visibility – Know state of device and actions available
 -  Feedback – Sending information back to the user about what action has been done and what has been accomplished
 -  Constraints – Restricting the possible user actions that can be performed
 -  Consistency – Design interfaces to have similar operations and use similar elements for achieving similar tasks
 -  Affordance – Attribute of an object that allows people to know how to use it
 
	 
	
	
	
	
		 
	 
		
Just another Kyoung Shin Park’s Lectures Sites site