What is deep learning?

Deep learning is best defined as a subset of machine learning that specifically utilizes multi-layered neural networks to learn from data. This approach allows the models to automatically discover patterns and features from raw inputs, such as images, text, or sound, without the need for manual feature engineering. The architecture typically involves many layers, which enable the system to build complex representations of data by stacking layers of nodes where each layer learns increasingly abstract features.

This structured approach allows deep learning models to excel in tasks such as image recognition, natural language processing, and automated decision-making, as they can capture intricate details that simpler models might miss. The multi-layered aspect is what differentiates deep learning from traditional machine learning methods that often use fewer layers and rely more heavily on handcrafted features. Therefore, the definition provided in the correct answer accurately reflects the essence of deep learning, highlighting its complexity and capability in processing vast amounts of data through deep neural architectures.