tf.keras is TensorFlow's implementation of the Keras API specification. This is a high-level API to build and train models, which includes first-class support for TensorFlow-specific functionality, such as eager execution, tf.data pipelines, and estimators. tf.keras makes TensorFlow easier to use without sacrificing flexibility and performance.
Keras (the original website that defines the Keras API standard) has been an open source project that got tremendous attention from ML engineers and data scientists due to its simplicity and strength. Initially, the default backend engine for Keras (remember, Keras is a set of APIs) was Theano; however, lately, it has changed, with TensorFlow now as its default backend engine. You can also set the default backend engine to MXNet, CNTK, and so on. Keras APIs are extremely user-friendly, modular, and composable...
