Google's 'Gemma 4' is currently undergoing testing within a chatbot arena. A notable component of this model is a 120-billion parameter Mixture-of-Experts (MoE) architecture. The MoE model is a type of neural network that utilizes multiple specialized "expert" sub-networks and a "gating network" to selectively activate a subset of these experts for a given input, allowing for a high total parameter count while maintaining computational efficiency during inference and training.