What type of contract is characterized as "one-sided" where only one party makes promises?

A unilateral contract is defined by its nature of being "one-sided," where only one party makes a promise that is contingent upon the performance of an act by the other party. In this context, the offeror makes a promise to do something in exchange for a specific act from the offeree, who is not required to make any promises in return. A classic example of a unilateral contract is a reward contract, where someone offers a reward for the return of lost property. The person finding and returning the property does not need to make a promise to find it, but once they do, the offeror is bound to fulfill the promise of the reward.

This characteristic distinguishes unilateral contracts from other types of agreements where both parties typically create mutual obligations and responsibilities. Understanding this fundamental principle is crucial in differentiating between various contract types and their applications in the realm of insurance and personal lines.