GPT-3.5 is one of a class of language models that are sometimes called “large language models” (LLMs)
ChatGPT itself Developed by OpenAI; based on GPT-3.5 with specialized training. An API for ChatGPT is available.
GPT-2, 3, 3.5, and 4 Large language models developed by OpenAI. GPT-2 is open source. GPT-3 and GPT-4 are not open source, but are available for free and paid access. The user interface for GPT-4 is similar to ChatGPT.
Sydney The internal code name of the chatbot behind Microsoft’s improved search engine, Bing. Sydney is based on GPT-4,1 with additional training.
Kosmos-1 Developed by Microsoft, and trained on image content in addition to text. Microsoft plans to release this model to developers, though they haven’t yet.
LaMDA Developed by Google; few people have access to it, though its capabilities appear to be very similar to ChatGPT. Notorious for having led one Google employee to believe that it was sentient.
PaLM Also developed by Google. With three times as many parameters as LaMDA, it appears to be very powerful. PaLM-E, a variant, is a multimodal model that can work with images; it has been used to control robots. Google has announced an API for PaLM, but at this point, there is only a waiting list.
Chinchilla Also developed by Google. While it is still very large, it is significantly smaller than models like GPT-3 while offering similar performance.
Bard Google’s code name for its chat-oriented search engine, based on their LaMDA model, and only demoed once in public. A waiting list to try Bard was recently opened.
Claude Developed by Anthropic, a Google-funded startup. Poe is a chat app based on Claude, and available through Quora; there is a waiting list for access to the Claude API.
LLaMA Developed by Facebook/Meta, and available to researchers by application. Facebook released a previous model, OPT-175B, to the open source community. The LLaMA source code has been ported to C++, and a small version of the model itself (7B) has been leaked to the public, yielding a model that can run on laptops.
Stable Diffusion An open source model developed by Stability AI for generating images from text. A large language model “understands” the prompt and controls a diffusion model that generates the image. Although Stable Diffusion generates images rather than text, it’s what alerted the public to the ability of AI to process human language.