DeepSeek is a generative AI chatbot developed by the Chinese company DeepSeek, released on 20 January 2025, which quickly surpassed ChatGPT as the most-downloaded free app on the US iOS App Store by 27 January. Its success triggered an 18% drop in Nvidia's share price and was hailed as a "Sputnik moment" for American AI, sparking what many describe as a global AI space race. The model is remarkably efficient, trained on only about 2,000 Nvidia H800 GPUs for roughly $5.58 million—about one-tenth of Meta's cost—and is praised for its open weights, energy efficiency, and contributions to open-source AI. However, its compliance with Chinese government censorship and data collection practices have raised privacy and information-control concerns, prompting regulatory scrutiny in multiple countries. Users can access the chatbot for free, with an API priced at about $0.28 per million input tokens, and DeepSeek has since released advanced models like DeepSeek-GRM, DeepSeek-Prover-V2-671B, and DeepSeek V4. Overall, it represents a major challenge to US AI dominance while democratizing access to cutting-edge artificial intelligence.