Voice User Interface

An interface that allows users to interact with a device or application through spoken language commands rather than touch, mouse, or keyboard input. Voice user interfaces use automated speech recognition (ASR) to convert speech to text and natural language understanding (NLU) to interpret user intent. In accessibility, VUIs are important for users with motor disabilities who cannot use touch or mouse input, for blind users who benefit from hands-free interaction, and for situationally impaired users (e.g., while driving). Commercial examples include Siri, Google Assistant, and Alexa, though these support only a limited subset of possible tasks. Research systems like AutoVCI demonstrate that voice interfaces can be automatically generated from recorded touch operation sequences, potentially extending voice control to any smartphone task.