OSI (Open Systems Interconnection) model is a standard reference model for communication between two end users in a network. It consists of seven layers, namely Physical, Data-link, Network, Transport, Session, Presentation and Application layers.
The data link layer, or layer 2, is the second layer of the seven-layer OSI model of computer networking. This layer is the protocol layer that transfers data between nodes on a network segment across the physical layer.
Please watch the following video for a brief explanation of the two Data Link Layer sublayers, LLC (Logical Link Control) and MAC (Media Access Control).
For more information on related topics, CCNA study notes available at