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ChatGPT launched in November 2022 and rapidly became the fastest consumer product to reach 100 million users in history. It's built on GPT (Generative Pre-trained Transformer) models, which are trained on enormous volumes of text to predict the most useful next word in a sequence. The result is a system that can hold coherent multi-turn conversations and produce surprisingly capable written output.
In practice, ChatGPT handles a wide range of tasks: answering factual questions, summarizing long documents, writing and debugging code, drafting emails or essays, translating languages, brainstorming ideas, and explaining difficult concepts in plain language. The free tier (GPT-3.5) is available at chat.openai.com; the paid ChatGPT Plus tier ($20/month) gives access to GPT-4o, which is significantly more capable.
There are real limitations. ChatGPT can produce confident-sounding but factually wrong answers — a problem called "hallucination." Its training data has a knowledge cutoff, so it may not know about very recent events. It also doesn't browse the web by default unless given a tool to do so, meaning it works from memorized training knowledge rather than live information.
ChatGPT is one of several capable AI assistants now available. Alternatives include Google's Gemini, Anthropic's Claude, and Meta's Llama-based tools. Each has different strengths, pricing tiers, and safety philosophies — it's worth trying more than one for your specific use case.
For everyday use, the most important habit is to verify any factual claim ChatGPT makes against a primary source before acting on it, especially for health, legal, or financial information.