Also known as: Chat Generative Pre-training Transformer
Written by Erik Gregersen
Fact-checked by The Editors of Encyclopaedia Britannica
Last Updated: Mar 19, 2025
ChatGPT, software that allows a user to ask it questions using conversational, or natural,
language. It was released on November 30, 2022, by the American company OpenAI and
almost immediately disturbed academics, journalists, and others because of concern that it
was impossible to distinguish human- from ChatGPT-generated writing.
Language models produce text based on the probability for a word to occur based on
previous words in the sequence. By being trained on about 45 terabytes of text from
the Internet, the GPT-3 language model used by ChatGPT calculates that some sequences of
words are more likely to occur than others. For example, “the cat sat on the mat” is more
likely to occur in English than “sat the the mat cat on” and thus would be more likely to
appear in a ChatGPT response.
ChatGPT refers to itself as “a language model developed by OpenAI, a leading artificial
intelligence research lab.” The model is based on the “GPT (Generative Pre-training
Transformer) architecture, which is a type of neural network designed for natural
language processing tasks.” ChatGPT says its primary purpose “is to generate human-like
text, which can be used for a variety of applications, such as chatbots, automated content
creation, and language translation.” It continues by saying “The model can understand and
respond to user input in a way that mimics human conversation, allowing for more natural
and engaging interactions. Additionally, ChatGPT can generate text in a variety of styles and
formats, such as news articles, emails, and poetry, making it versatile and useful for a wide
range of applications.”
ChatGPT impressed many with its command of written English and as a demonstration of
how far artificial intelligence (AI) had advanced. Within five days of its introduction, more
than one million users had signed up for a free account to interact with ChatGPT. The
software showed that it could pass exams in advanced courses. For example, Wharton
Business School professor Christian Terwiesch found that ChatGPT passed the final exam in
his course in operations management.
Although ChatGPT had many strong attributes, it also has some surprising weaknesses. The
model can add two-digit numbers (e.g., 23 + 56) with complete accuracy, but for multiplying
two-digit numbers (e.g., 23 × 56), it produces the right answer only about 30 percent of the
time. Like other large language models, ChatGPT can sometimes “hallucinate,” a term used
to describe the tendency for such models to respond with inaccurate or misleading
information.
ChatGPT, at least, recognizes its limitations. When asked if it is a reliable source of
information, it replies that “it is not recommended to rely on ChatGPT as a sole source of
factual information. Instead, it should be used as a tool to generate text or complete
language-based tasks, and any information provided by the model should be verified with
credible sources.”
Source: https://www.britannica.com/technology/ChatGPT
