# Observers

BlueBase provides observer components. They observe different aspects of application state so relevant UI state can be rendered. 

There are currently four observer components:

1. [DataObserver](https://bluebase.gitbook.io/core/components/observers/dataobserver)
2. [ErrorObserver](https://bluebase.gitbook.io/core/components/observers/errorobserver)
3. [HoverObserver](https://bluebase.gitbook.io/core/components/observers/hoverobserver)
4. [WaitObserver](https://bluebase.gitbook.io/core/components/observers/waitobserver)