PyTorch is an open-source machine learning library primarily developed by Facebook’s AI Research lab. It is designed for building and training deep learning models, offering a flexible and intuitive interface that appeals to both researchers and developers. PyTorch stands out due to its dynamic computational graph, which allows for real-time changes to the network architecture during execution, making it easier to experiment with complex models. With robust support for tensor operations and automatic differentiation, PyTorch is widely used in academia and industry, competing closely with other frameworks like TensorFlow. Its user-friendly nature and rich ecosystem make it a popular choice for deep learning projects.