An integration is your account-level connection to a third-party service like Google, Notion, or YNAB.
Before you can create a destination (e.g. a specific Google Sheet), you first need to connect the integration by signing in with that service. This is a one-time OAuth sign-in step.
Once an integration is connected, you can create multiple destinations from it. For example, connecting your Google account once lets you create as many Google Sheets destinations as you need.
You can manage your integrations from the Integrations page in the dashboard. If an integration's token expires, you can reconnect it from there.