Towards a human-computer interaction model for voice user interfaces

The user interaction with computer systems has evolved over the years, from Command Line Interfaces (CLIs), Graphics User Interfaces (GUIs), Natural User Interfaces (NUIs) and actually Voice User Interfaces (VUIs). The use of VUIs is increasingly common, increasing user attention, facilitating the execution of tasks of users with non-technical training and taking advantages that hands and eye free interfaces provide in many situations. However, it is necessary to identify which elements are essentials for a great user experiences, what attributes need to be evaluated and which HCI testing methods apply to evaluate them.