Keras is a high-level neural network Application Programming Interface (API) written in Python that simplifies debugging and studying neural networks. This open-source neural network toolkit is based on CNTK, TensorFlow, and Theano and may be used to experiment with deep neural networks fast. Its API is high-level, user-friendly, modular, and extensible, allowing for fast experimentation. Keras is a programming language that can be used on both the CPU and the GPU.