ACD stands for Automatic Call Distributor. An automatic call distributor (ACD) is a system that is used to route incoming telephone calls to the appropriate destination. ACD systems are typically used in call centers and other environments where a large volume of incoming calls needs to be handled efficiently. ACD systems use a variety of algorithms and rules to determine how calls should be routed, based on factors such as the caller's location, the time of day, the caller's history, and the availability of agents. ACD systems can also provide a range of other features and functions, such as call queuing, call tracking, and reporting, to help improve the efficiency and effectiveness of call centers.