You've been eying that 60-inch television in the appliance store window for weeks. Finally, it's payday, and you sprint to the store and make the purchase. It's simple. Fork over the cash and walk away with your very own television. See, the promisor, the appliance store, promised to give you a spanking new TV for $500, and you, the promisee, promised to pay for it. Done!
This is an example of an executed contract; a contract in which the promises are made and completed immediately, like in the purchase of a product or service. On the other hand, an executory contract means that the promises of the contract are not fully performed immediately. An example of an executory contract would be an apartment lease.
When you enter into a lease agreement, you are promising to pay the rent for a period of time. Until the term expires, the contract promises have not been fulfilled. Put another way, a landlord generally rents an apartment under a lease contract. This agreement identifies the name of the person leasing or renting, the name of the landlord, the terms and conditions, the length of lease and the monthly rental fee for occupying the space.
A lease cannot be fulfilled in one single transaction, like buying a television. Since a lease is usually written for a period of one year, it is an executory contract, because it is fulfilled over time. In general, an executed contract is a done deal. On the other hand, an executory contract isn't fulfilled right away, leaving time for things to go wrong.