Creating a feature can be a time-consuming activity and you need it to be available for both offline and online activities. Furthermore, a feature you have created for one purpose may well be relevant for another task. A feature store is a component that manages the ingestion of raw data (from databases, event streams etc.) and turns it into features which can be used both to train models and as an input to the operational model. It takes the place of the data warehouse and the operational data pipelines - providing a batch API or query mechanism for retrieval of feature data-sets for model training, as well as a low latency API to provide data for real-time predictions.