Megatron-LM is a powerful transformer developed by NVIDIA's Applied Deep Learning Research team. It is used for training large transformer language models at scale. The tool supports model-parallel, tensor-parallel, and pipeline-parallel training of models like GPT, BERT, and T5. Megatron-LM enables efficient and distributed pre-training of these models using mixed precision. It has been used in various projects for tasks such as language modeling, question answering, and information retrieval.