Short answers, pulled from the story.
ChatGPT was originally released in November 2022. It gained one million users in five days and one hundred million monthly active users within two months, making it the fastest-growing internet application in history at the time. By February 2026, it had reached nine hundred million weekly active users.
Hallucinations are instances where ChatGPT presents nonsense or misinformation as fact. A 2023 analysis estimated that ChatGPT hallucinates around three percent of the time. The phenomenon is more similar to confabulation than to the psychological meaning of hallucination.
ChatGPT was trained using supervised learning and reinforcement learning from human feedback (RLHF). To build a content safety filter, OpenAI contracted Sama, a San Francisco-based company, which employed Kenyan workers earning around $1.32 to $2 per hour to label harmful content including child sexual abuse material, torture, and self-harm. Team leader Richard Mathenge and quality-assurance analyst Mophat Okinyi reported lasting psychological harm from the work.
Italy's data protection authority banned ChatGPT in late March 2023 over potential GDPR violations and concerns about minors accessing age-inappropriate content. The ban was lifted in April 2023 after OpenAI implemented age verification and clarified its privacy policy. ChatGPT has never been publicly available in China, as OpenAI blocked Chinese users from the outset.
In January 2023, Nick Cave responded on his newsletter The Red Hand Files after being sent a song ChatGPT wrote in his style. He called it "bullshit, a grotesque mockery of what it is to be human" and described songwriting as "a blood and guts business" requiring his humanness to initiate new and fresh ideas.
TrendForce estimated that in 2023, thirty thousand Nvidia GPUs each priced at approximately ten to fifteen thousand dollars were used to power ChatGPT. The system initially ran on a Microsoft Azure supercomputer built specifically for OpenAI at a cost of hundreds of millions of dollars. Scientists at the University of California, Riverside, estimated that a series of five to fifty prompts to ChatGPT requires approximately 0.5 liters of water for server cooling.