Llama 2 is Meta's second-generation open-source large language model, available in 7B, 13B, and 70B parameter sizes, with both pretrained and fine-tuned chat variants. Unlike the original LLaMA, Llama 2 is released for both research and commercial use under a permissive license. The chat-optimized versions use RLHF alignment and are competitive with many proprietary models on reasoning and dialogue benchmarks.
