| Comparison Criteria | PyTorch | TensorFlow | Keras | 
| Developer | Developed by Facebook’s AI Research lab | Developed by the Google Brain team | Initially developed by François Chollet, now part of TensorFlow | 
| Release Year | 2016 | 2015 | 2015 (integrated into TensorFlow in 2017) | 
| Computation Graph | Dynamic computation graph (define-by-run) | Static computation graph (define-and-run) | High-level API built on top of TensorFlow’s static graph | 
| Ease of Use | User-friendly, especially for Python developers | Steeper learning curve due to extensive features | Very easy to use with simple and intuitive syntax | 
| Flexibility | Highly flexible, ideal for research and experimentation | Flexible but can be complex for beginners | Less flexible, best for standard neural network models | 
| Performance | Efficient for research and small to medium projects | Optimised for large-scale deployments and production environments | Good performance for prototyping and small projects | 
| Debugging | Easier to debug with dynamic graphs | More challenging due to static graphs | Easier debugging through TensorFlow backend | 
| Model Deployment | Improving with TorchServe, but traditionally less robust than TensorFlow | Strong deployment options with TensorFlow Serving and TensorFlow Lite | Leverages TensorFlow’s deployment tools for easy model serving | 
| Community Support | Large and active community, especially in academia | Extensive community support with numerous resources | Strong community support, especially among beginners | 
| Documentation | Comprehensive and continuously improving | Extensive and detailed documentation | Clear and beginner-friendly documentation | 
| Pre-trained Models | Available through Torchvision and other libraries | A vast repository of pre-trained models on TensorFlow Hub | Access to TensorFlow’s pre-trained models via Keras Applications | 
| Integration with Other Tools | Integrates well with Python libraries and tools | Integrates with a wide range of tools and platforms | Seamlessly integrates with TensorFlow and its ecosystem | 
| Learning Curve | Moderate, easier for those familiar with Python | Steeper, especially for complex applications | Gentle, ideal for beginners | 
| Popular Use Cases | Research, prototyping, computer vision, natural language processing | Large-scale machine learning, production systems, mobile applications | Rapid prototyping, educational purposes, simple neural networks | 
| API Design | Pythonic and intuitive API | Comprehensive but can be verbose API | Simplified and user-friendly API | 
| Extensibility | Highly extensible with custom layers and operations | Highly extensible with TensorFlow Addons and custom operations | Limited extensibility, best for standard model architectures |