GPT(GPT)
The name of the family of AI models made by OpenAI that power ChatGPT. The letters stand for Generative Pre-trained Transformer, which describes how the models are built: they generate text, they are trained in advance on huge amounts of writing, and they use a design called a transformer. In everyday use, "GPT" usually refers to one of these specific models.
GPT is a series of large language models built by the company OpenAI. When people mention GPT-4 or a similar name, they are talking about a particular version of this model family. ChatGPT, the popular chat tool, runs on these models, which is where much of the name recognition comes from.
The three words behind the abbreviation each describe something real. “Generative” means it produces new text rather than picking from fixed answers. “Pre-trained” means it has already learned from an enormous amount of writing before you ever type anything. “Transformer” is the name of the underlying design that makes modern language models work so well.
It is worth knowing that GPT is a brand, not a general term for all AI. Claude, Gemini, and Llama are made by other companies and are not GPT models, even though they do similar things. People sometimes use “GPT” loosely to mean “an AI chatbot,” but strictly speaking it points to OpenAI’s models in particular.
For you as a beginner, the practical takeaway is that a version number tells you something. A newer GPT model is generally more capable than an older one, and the tool you are using will usually say which version it runs on somewhere in its settings or its documentation.