OpenAI logo, creators of ChatGPT

ChatGPT: AI Goes Mainstream

What Happened

OpenAI released ChatGPT, a conversational AI based on GPT-3.5 fine-tuned with RLHF (Reinforcement Learning from Human Feedback). It reached 1 million users in 5 days and 100 million in 2 months — the fastest-growing consumer application in history. People used it to write emails, debug code, brainstorm ideas, and a thousand other tasks.

Why It Mattered

The defining consumer moment of the modern AI era. ChatGPT didn't just introduce AI to the public — it made AI feel personal, useful, and immediate. It triggered a global AI investment boom and fundamentally changed how the world thought about technology, work, and machine intelligence.

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