The aim of ChainLink is to enable blockchains to interact with the real world.
through a set of APIs, ChainLink creates an Oracle which communicates real world information to blockchains and smart contracts. In order to access details via ChainLink, users initially should provide a request contract.
ChainLink uses that contract to locate the necessary Oracle for the required information. Users define the specified criteria for how they expect the outcome to be obtained. This is referred to as the Service Level Agreement (SLA). Details in the SLA can include the required reputation of Oracle and the number of Oracles required. The Oracles send back to the contract the outcome of the SLA. The aggregate contract incorporates the information sent by all Oracles. The end product is a weighted average of all Oracles' responses. Evey Oracle has credibility founded on its background of integrity.
Many Oracle responses are consolidated collectively to generate a specific result, that is submitted to the requester.