Generative AI systems—like ChatGPT and Bard—create text, images, audio, video, and other content. This Spotlight examines the technology behind these systems that are surging in popularity. These systems are trained to recognize patterns and relationships in massive datasets and can quickly generate content from this data when prompted by a user. These growing capabilities could be used in education, government, medicine, law, and other fields. But these systems can also generate "hallucinations"—misinformation that seems credible—and can be used to purposefully create false information. Other challenges include oversight and privacy concerns.