PyTorch is a powerful open-source deep learning framework developed by Facebook's AI Research lab. It has quickly become popular among developers and researchers as it offers all the features and flexibility needed for deep learning applications. PyTorch's modular, production-ready, and user-friendly API makes it easy to develop and deploy deep learning models. It also features a rich set of libraries and tools for efficient model training and development. PyTorch is also highly scalable, allowing for easy integration with popular deep learning libraries and frameworks like TensorFlow, Caffe2, and Theano. With its intuitive and simple API, PyTorch is a great choice for developers and researchers looking to get started with deep learning.