SciPy is a powerful Python library used for mathematical and scientific computing. In the context of machine learning, SciPy provides a wide range of tools and functions that facilitate data manipulation, model building, and analysis. It includes modules for optimization, linear algebra, integration, interpolation, special functions, FFT, signal and image processing, and more. W3Schools offers tutorials and resources that help learners understand and implement these functionalities in practical machine learning projects, making it a valuable resource for both beginners and advanced users looking to enhance their data science skills.