PyTorch is an open-source machine learning library primarily developed by Facebook’s AI Research group. It is widely used for building and training deep learning models due to its flexibility and ease of use. PyTorch employs dynamic computation graphs, allowing developers to modify the network behavior on-the-fly, which is particularly beneficial for complex architectures. The library is designed to be intuitive, leveraging core Python concepts, making it accessible for both beginners and experienced practitioners. With strong support from the research community, PyTorch is gaining popularity in both academic and production environments for various AI applications.