Imagine having an assistant available 24/7, capable of answering questions, writing texts, explaining complex concepts, assisting with programming code, and even creating scripts — all in seconds and in English. This is not science fiction: it’s exactly what ChatGPT offers, and millions of people are already using this tool daily without paying a dime.
Launched in November 2022 by the American company OpenAI, ChatGPT has become one of the fastest-growing tech products in history. Just months after its launch, it surpassed 100 million active users, solidifying the concept of generative artificial intelligence in popular vocabulary. Since then, the tool has evolved significantly, offering paid versions with advanced features while maintaining a free option that remains extremely useful for most everyday uses.
If you’re still unsure what ChatGPT is, how it works, or where to start, this guide is for you. We’ll explain everything clearly, without unnecessary jargon, and show you how to make the most of the tool’s free version.
What Exactly is ChatGPT?
ChatGPT is a large language model (LLM) developed by OpenAI. In simple terms, it’s a computer program trained with vast amounts of text — books, articles, websites, forums, and more — to learn patterns of human language and, from there, generate coherent and contextualized responses.
The acronym GPT stands for Generative Pre-trained Transformer, which describes the technical architecture behind the system. But the most important thing for the average user is not the acronym: it’s what it does in practice. You write a message (called a prompt), and ChatGPT responds as if it were a conversation — hence the “Chat” in the name.
Unlike a search engine like Google, which lists links and pages, ChatGPT synthesizes information and generates new text, as if it were “thinking” of the answer for you. This makes it useful for tasks that require creativity, synthesis, or explanation — not just information retrieval.
How Does ChatGPT Learn and Respond?
To understand ChatGPT, it’s helpful to know the basics of how it was built. The model underwent two major training stages:
- Pre-training: The model was exposed to billions of texts and learned to predict which word comes next in a sequence. This allowed it to internalize grammar, facts, writing styles, and even logical reasoning.
- Fine-tuning with human feedback (RLHF): Human reviewers evaluated the model’s responses and indicated which were better. This process helped make ChatGPT more useful, safe, and aligned with what people really need.
The result is an AI capable of maintaining long conversations, remembering the context of previous messages within the same session, and adapting the tone according to the request — more formal, more relaxed, more technical.
It’s important to highlight a significant limitation: ChatGPT has a knowledge cutoff, meaning it doesn’t have real-time internet access in its standard version. This means it may not be aware of very recent events. Some more advanced versions, available in the paid plan, allow web browsing, overcoming this limitation.
Free and Paid Versions: What’s the Difference?
OpenAI offers ChatGPT in different plans. In 2026, the basic structure is as follows:
- Fine-tuning with human feedback (RLHF): Human reviewers evaluated the model’s responses and indicated which were better. This process helped make ChatGPT more useful, safe, and aligned with what people really need.
