ChatGPT is an artificial intelligence chatbot developed by OpenAI and launched in November 2022. It is built on top of OpenAI's GPT-3 and GPT-4 families of large language models and has been fine-tuned (an approach to transfer learning) using both supervised and reinforcement learning techniques.
https://openai.com/blog/chatgpt
OpenAI Codex is an artificial intelligence model developed by OpenAI. It parses natural language and generates code in response. It is used to power GitHub Copilot, a programming autocompletion tool developed for select IDEs, like Visual Studio Code and Neovim. Codex is a descendant of OpenAI's GPT-3 model, fine-tuned for use in programming applications.
https://openai.com/blog/openai-codex/
DALL·E is a 12-billion parameter version of GPT-3 trained to generate images from text descriptions, using a dataset of text–image pairs.
https://openai.com/blog/dall-e-now-available-without-waitlist