An LLM is an artificial intelligence model trained on vast amounts of text to predict and generate language coherently. Its operation is based on the Transformer architecture, which allows it to analyze the relationships between words within a context and anticipate the most likely continuation of a sequence. The adjective "large" refers to both the volume of training data and the number of parameters, which can number in the billions.
Their importance lies in the fact that they form the basis of today's conversational assistants, such as ChatGPT, Gemini, or Claude. Beyond conversation, they are used for very diverse tasks:
- Writing and summarizing texts.
- Translation between languages.
- Code generation and debugging.
It is worth remembering a practical nuance: an LLM does not "understand" in the human sense, nor does it consult a database of truths; instead, it generates statistically plausible text. This is why it can produce hallucinations, that is, false statements expressed with total confidence, something that makes it necessary to always verify sensitive information.