The Radix Network itself natively understands the concept of resources, and you can think of them as like “physical objects” on the ledger. This is enforced via the Radix Engine execution environment that guarantees that resources should behave as we would intuitively imagine them to, such as a resource can only be in one place at a time, that it can’t be spent twice, that it can’t get lost or go missing as part of a transaction.
Each resource has a unique address, e.g. the resource address for XRD is resource_rdx1tknxxxxxxxxxradxrdxxxxxxxxx009923554798xxxxxxxxxradxrd
You can query these resources on the Radix Dashboard.