Hey @naveenkumar1
Direct Call Rules are something used within Adobe Launch, the tag management system.
A direct call event bypasses event detection and lookup systems. Direct call rules are ideal for situations where you want to tell the system exactly what is happening. Also, they are ideal when the system cannot detect an event in the DOM.
When defining a direct call event, you must specify a string that will act as this event’s identifier. If a trigger direct call action containing the same identifier is fired, then any direct call event rules listening for that identifier will run.
CEDDL & EDDL are both data layers.
A good way to remember the difference is the CEDDL is 25% more difficult to spell and to implement.
The Event-Driven Data Layer describes what you’re implementing: a data layer that is constructed and transmitted to your TMS by events.
ACDL - Adobe Client Data Layer is Adobe's event driven data layer built on Adobe Experience Manager(AEM)