The Trustee's Report of No Distribution, or NDR, lets the court and all interested parties know that no money will be paid to creditors. If a NDR is filed, the court will close the bankruptcy case shortly after the discharge has been entered.
The typical NDR beings like this:
I, TRUSTEE NAME, having been appointed trustee of the estate of the above-named debtor(s), report that I have neither received any property nor paid any money on account of this estate; that I have made a diligent inquiry into the financial affairs of the debtor(s) and the location of the property belonging to the estate; and that there is no property available for distribution from the estate over and above that exempted by law. Pursuant to Fed R Bank P 5009, I hereby certify that the estate of the above-named debtor(s) has been fully administered. I request that I be discharged from any further duties as trustee.
If the trustee determines that you have nonexempt assets, they will not file a NDR. Instead, they'll file a notice to give creditors a deadline to file a proof of claim in your case. More on that here.