# Development The class structure and details algorithmic overview is depicted in the following diagram: ![image](assets/freqai_algorithm-diagram.jpg) As shown, there are three distinct objects comprising `FreqAI`: * IFreqaiModel * Singular persistent object containing all the necessary logic to collect data, store data, process data, engineer features, run training, and inference models. * FreqaiDataKitchen * A non-persistent object which is created uniquely for each unique asset/model. Beyond metadata, it also contains a variety of data processing tools. * FreqaiDataDrawer * Singular persistent object containing all the historical predictions, models, and save/load methods. There are a variety of built-in prediction models which inherit directly from `IFreqaiModel` including: * CatboostRegressor * CatboostRegressorMultiTarget * CatboostClassifier * LightGBMRegressor * LightGBMRegressorMultiTarget * LightGBMClassifier * XGBoostRegressor * XGBoostRegressorMultiTarget * XGBoostClassifier Each of these have full access to all methods in `IFreqaiModel`. And can therefore, override any of those functions at will. However, advanced users will likely stick to overriding `fit()`, `train()`, `predict()`, and `data_cleaning_train/predict()`.