# V2 API Overview

The PaddlePaddle V2 API is designed to provide a modern user interface for PaddlePaddle V1(the original layer-based platform of PaddlePaddle), it proposes some high-level concepts such as Layers , Optimizer , Evaluator and Data Reader to make the model configuration more familiar to users.

A model is composed of the computation described by a group of Layers, with Evaluator to define the error, Optimizer to update the parameters and Data Reader to feed in the data.

We also provide the interface for Training and Inference to help control the training and inference phrase, it has several easy to use methods to better expose the internal running details, different events are available to users by writing some callbacks.

All in all, the V2 API gives a higher abstraction and make PaddlePaddle programs require fiew lines of code.