A creditor holds a debt owed to him or her by a debtor. When the creditor sues the debtor in order to recover the debt owed, the creditor becomes a plaintiff and the debtor becomes the defendant. If the plaintiff prevails on the claim, then the plaintiff becomes the judgment creditor and the defendant becomes the judgment debtor, and the debt is said to be “reduced to judgment” – so that what the judgment creditor holds is a judgment, not merely a debt.
A judgment is usually final and collectible as soon as it is entered. In fact, a judgment is not appealable until it is final: a judgment that is not final is known as an “interlocutory” judgment and, with a few limited exceptions, is not appealable. (Some jurisdictions require a brief automatic stay after entry of judgment, commonly for 10 days – but not until the right of appeal is exhausted, which usually takes at least 30 days and in some cases as long as 180 days even if the judgment debtor does not exercise that right. See, e.g., Fed. R. App. P. 4(a)(6)(A). A judgment creditor in most cases can collect the judgment, even if the judgment debtor has taken an appeal, unless the judgment debtor posts two bonds: an appeal bond, guaranteeing payment of costs on appeal; and a supersedeas bond, guaranteeing payment of the judgment itself in case the judgment creditor prevails on appeal. For example, the Federal Rules of Appellate Procedure, after which most states also model their appellate rules, cover this topic in Rules 7-8.)
A judgment is itself essentially an “order to pay.” The judgment authorizes the issuance of new process, usually known as an execution (or an order for execution or writ of execution), which empowers the sheriff (or, in some cases, the judgment creditor or his or her attorney) to seize assets or other property belonging to the judgment debtor in satisfaction of the judgment. The judgment invokes the power of the state in aid of executing and satisfying the judgment: basically, it says that the state (usually in the person of the sheriff) may forcibly seize assets from the judgment debtor for that purpose, regardless of the judgment debtor’s consent. A judgment debtor must appear and testify, produce documents, or furnish information under oath about his or her assets if the judgment creditor so demands. A judgment debtor may go to jail for forcibly interfering with an execution, for failing to furnish properly demanded information, or for spiriting assets out of the jurisdiction, but not for nonpayment.
Most jurisdictions let the judgment creditor levy an execution upon whatever non-exempt assets he or she or the sheriff (who usually relies on the judgment creditor’s information, rather than going out and actively discovering the judgment debtor’s assets) can find, including wages, so that exhausting other assets is not necessary before garnishing wages. (Technically, garnishing wages is a new lawsuit, since it involves assets – the wages – in the hands of a stranger to the lawsuit between the judgment creditor and the judgment debtor. The judgment creditor must typically serve a garnishment summons upon the garnishee, with notice to the judgment creditor, so that they each enjoy an opportunity for asserting any available legal objection to the garnishment.)
An additional proceeding is necessary only if the judgment creditor is seeking assets in a jurisdiction where the court’s writ does not run, in which case the judgment creditor must record the judgment in a court in that jurisdiction. But at least throughout the United States, the Full Faith and Credit Clause requires that “full faith and credit shall be given in each state to the public acts, records, and judicial proceedings of every other state.” (U.S. Const., art. IV, § 1.) So the out-of-state court must likewise honor the judgment, and recording it is mostly a formality.
The judgment debtor either has the resources for satisfying the judgment, in which case the judgment creditor and the sheriff can take them, with or without the judgment debtor’s cooperation; or the judgment debtor doesn’t, in which case the judgment debtor is “judgment proof,” and the judgment creditor is essentially s.o.l. As far as I know, there is no jurisdiction in the United States where an unsatisfied judgment by itself can land the judgment debtor in prison.
Some states have set up funds that will reimburse an unsatisfied judgment in certain cases, such as malpractice or civil damage resulting from criminal activity, but state-sponsored reimbursement is the exception rather than the rule.