Meta Releases Llama 2

Meta released Llama 2 in July 2023 with 7, 13, and 70 billion parameter versions and a license that permitted many commercial uses. That was a major change from the research-only distribution of the first LLaMA.

The chat variants were trained with supervised fine-tuning and reinforcement learning from human feedback. Meta also increased the context length and training data compared with the first generation.

Because the weights were downloadable, companies could host the model themselves, quantize it to use less memory, or fine-tune it on private data. Llama 2 strengthened a parallel AI ecosystem in which capable models could run outside the APIs of OpenAI, Google, or Anthropic.