[Important: to determine whether a contract is unilateral or bilateral, courts will often check whether each party has offered a certain value – in this case, the contract is bilateral.] Contracts are described on the basis of four criteria and are therefore defined: expressiveness (express, tacit or quasi-contracts), reciprocity (bilateral or unilateral), applicability (not applicable, not applicable) and level of conclusion (execution, partially executed, executed). Legal terminology in English often describes the relationships between the parties by the use of suffixes that the eye and ear must monitor. Both parties to a bilateral agreement make promises. With regard to the promise at issue, the party making the promise is the promisor and the other part of the promises. The legal disadvantage of the promise lies in another promise on his part to do something or to abstain from something that he has not been kept by law or that he refrains from doing. This legal damage is a consideration, cause, motive or usefulness that leads to the conclusion of a contract. Consideration is an essential part of a contract. For example, if someone offered to drive you to work on Mondays and Tuesdays in exchange for your promise to return favors on Wednesdays and Thursdays, a bilateral contract would bind you as soon as you thought about those conditions. But if the same person offered to pay you $10 a day that you would take him to work, a unilateral contract would be formed, which would only hire the promisor until you took him to work on a given day. An express contract is a contract that directly defines the terms and conditions. Parties to an explicit contract, written or oral, are aware that they are entering into an enforceable agreement.

For example, an agreement to buy your neighbor`s car for 5500 $US and take the title next Monday is an express contract. Traditionally, courts have distinguished between unilateral and bilateral agreements by establishing whether one or both parties have considered and when they have provided the consideration.