Prerequisites
The track call lets you record the customer events, i.e. the actions that they perform, along with any associated properties. The events collected can be used to trigger campaigns/workflows and also be synced to your data warehouse. A sample track call is shown below: 
castledanalytics.track(
  "Added to Cart",
  {
    value: 30,
    currency: "USD",
    item: "product A",
  },
  () => {
    console.log("in track call")
  }
)
  • event-name is a string to identify the user event
  • properties is a flat-map of event properties