Llama 2

Llama 2 is Meta's second-generation open-source large language model, released in July 2023 for both research and commercial use. As one of the most capable openly available language models, Llama 2 has become the foundation for an enormous ecosystem of derived models, fine-tunes, and applications that have democratized access to powerful language AI.

The model comes in multiple sizes — 7 billion, 13 billion, and 70 billion parameters — allowing users to choose the appropriate capability-to-resource tradeoff for their specific needs and hardware. The 7B model runs on consumer hardware with a modern GPU, while the 70B model requires more significant computational resources but delivers performance approaching closed commercial models.

Llama 2's open-source release with a commercial use license was a landmark moment in AI development, enabling companies and developers to build commercial products on top of powerful language models without recurring API costs or dependency on external providers. This has enabled a wave of AI application development particularly in privacy-sensitive and on-premises use cases.

The fine-tuning ecosystem built on Llama 2 is extraordinary in its breadth. Specialized models fine-tuned from Llama 2 cover domains including coding (Code Llama), medical question answering, legal analysis, creative writing, and many others. Community platforms like Hugging Face host thousands of Llama 2 derived models for specific use cases.

Meta has continued the Llama family with Llama 3, which further improves on performance and extends the model's capabilities. The Llama model family represents Meta's significant contribution to the open AI ecosystem and continues to influence the entire field of language model development.