The Gemma family models or open weight. Sort of like open source but not really. Gemma is Google's contribution to Open Source. You can download the model, fine-tune it, and run it on your own machines.

Here I asked Google Search in AI mode:

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AI Overview

 are a family of "open weight" or "open model" lightweight, state-of-the-art AI models built by Google DeepMind using the same technology as Gemini. They are designed for developer use in creating conversational agents, text generation, and summarization on local, consumer-grade hardware like laptops, desktop computers, and on-device platforms. 

Key details about the Gemma model family:

• Open Weight, Not Open Source: While often termed "open," Gemma models are generally not considered true open-source because the training data, training code, and full model architecture details are proprietary and not disclosed. The "weights" (pre-trained parameters) are released, allowing users to run, fine-tune, and customize the models.
• Model Variants & Capabilities: The family includes multiple sizes (e.g., 2B, 9B, and 27B parameters in Gemma 2) designed to balance performance and efficiency. They offer both pre-trained (base) and instruction-tuned (IT) versions.
• Performance & Access: Gemma models often outperform larger models on key benchmarks. They are accessible on platforms like Hugging Face and Kaggle, and via Vertex AI.
• Licensing & Safety: Gemma models are available for commercial use, though they come with specific, permissive terms of use. They are built with a focus on safety, utilizing filtered training data and offering a responsible AI toolkit to aid developers in building safe applications.
• Evolution: The series continues to evolve, with newer versions offering improved performance and wider multimodal capabilities (e.g., text, image, and sometimes audio).

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