# The hass object

> The `HomeAssistant` instance that integrations get, with access to the state machine, the event bus, actions, and the configuration.

Source: https://contributors.home-assistant.io/glossary/hass/

- In code: `HomeAssistant`, `hass`
- Also: hass

Almost every function in Home Assistant Core takes `hass` as its first argument. It is how code reaches everything else: `hass.states`, `hass.bus`, `hass.services`, and `hass.config`.

`hass` is a name in code. In text, write Home Assistant.

## Related terms

- [State machine](https://contributors.home-assistant.io/glossary/state-machine/): The part of Home Assistant Core that holds the current state of every entity.
- [Event](https://contributors.home-assistant.io/glossary/event/): A message on the event bus that something happened, like a state change or a button press. Any code can listen to events.
- [Action](https://contributors.home-assistant.io/glossary/action/): Something Home Assistant can do, like turning on a light or sending a notification. Automations, scripts, and dashboards perform actions.
- [Event loop](https://contributors.home-assistant.io/glossary/event-loop/): The asyncio loop that runs Home Assistant Core. Code that blocks it, like waiting on the network without `await`, stops everything else.