Microsoft Corporation unveiled a small language model named Mu on June 23, designed for local operation on personal computers, particularly Copilot+ PCs. Mu is a 330 million parameter encoder-decoder language model optimized for deployment on Neural Processing Units (NPUs), allowing for quick responses with reduced power consumption and memory usage. It was pre-trained on a dataset of hundreds of billions of educational tokens and employs advanced fine-tuning techniques, including distillation and low-rank adaptation, along with transformer enhancements like Dual LayerNorm, Rotary Positional Embeddings, and Grouped-Query Attention. Users will access Mu's capabilities through the Windows operating system's Settings function, translating natural language inputs into system commands.