PyTorch is a popular open-source machine learning framework (originating from Facebook’s AI Research lab) used for building and training deep learning models. It provides flexible tools for constructing neural networks and performing tensor computations with strong support for GPU acceleration​.PyTorch is built on the Torch library and is known for its dynamic computation graph approach – meaning the computational graph is built on-the-fly, which makes debugging and developing complex models more intuitive and Pythonic. Researchers and developers favor PyTorch for its ease of use in prototyping: one can define model layers and forward pass logic using standard Python control flow, and PyTorch handles backpropagation automatically with its autograd engine. The framework includes a rich ecosystem: the torch.nn module for layers and loss functions, torch.optim for optimization algorithms, and utilities for data loading (torch.utils.data). PyTorch has become one of the preferred platforms for deep learning research, allowing fast iteration from idea to implementation​.It’s also used in production; features like the TorchScript JIT compiler and TorchServe facilitate the deployment of models after the research phase​.Overall, PyTorch accelerates the path from research prototyping to production by providing an intuitive yet powerful interface for neural network development​.Examples of tasks built with PyTorch include image classification models, NLP transformers, reinforcement learning agents, and more – virtually any AI project that requires training neural networks can be implemented with PyTorch’s toolkit.