Executed contracts mean that all parties have performed all the obligations that they were required to. While in executory contracts, one or more obligations remain from either of the parties.
Example of executed contracts: You wanted to purchase a refrigerator. You went to the appliances shop, paid the money for it, and the shop handed your refrigerator to you. All parties fulfilled their obligations.
Example of Executory Contracts: For instance, an apartment lease as it is fulfilled over time.