A voice assistant is a type of virtual assistant that uses natural language processing and machine learning to recognize human speech and respond appropriately. It can perform tasks such as playing music, setting reminders or alarms, providing weather updates, making phone calls, sending text messages, controlling smart home devices, and answering questions based on user input. Voice assistants are typically integrated into smartphones, tablets, computers, and other electronic devices that have built-in microphones and speakers, allowing users to interact with them hands-free while performing other tasks. Some popular voice assistants include Siri (by Apple), Google Assistant (by Google), Amazon Alexa (by Amazon), and Microsoft Cortana (by Microsoft).