Contingent contracts and wagering contracts both involve future uncertain events, but they differ in important ways. Contingent contracts require the performance of a contract to be conditional on a future collateral event outside the control of the promisor. Examples include contracts for the sale of goods if they arrive safely by ship. Wagering contracts, which are void, involve money being paid based solely on an uncertain future event determined by chance alone, with both parties having equal chance of gain or loss but no other interest in the outcome. The key differences are that contingent contracts may involve other interests, while wagering contracts do not, and contingent agreements are not a game of chance like wagering agreements.