GPT stands for "Generative Pre-trained Transformer". It is a type of language model developed by OpenAI, a research organization dedicated to developing and promoting artificial intelligence in a safe and beneficial manner.

The GPT models are based on the transformer architecture, which is a type of neural network that is particularly well-suited for processing sequential data such as language. GPT models are "pre-trained", which means that they are first trained on a large corpus of text data before being fine-tuned on a specific task, such as language translation or text completion.

The pre-training process involves exposing the model to massive amounts of text data, such as books, articles, and web pages, and training it to predict the next word or sequence of words given a context. By doing this, the model learns to capture the statistical patterns and relationships in the language, which allows it to generate coherent and fluent text when given a prompt.

GPT models have been used in a variety of applications, such as text completion, chatbots, and language translation. The most advanced GPT model to date is GPT-3, which has 175 billion parameters and has demonstrated impressive performance on a range of language tasks.