Final answer:
NICs encapsulate data into a frame for network transmission, adding necessary headers and footers for addressing and error checking before sending the data.
Step-by-step explanation:
NICs (Network Interface Cards) encapsulate data into a frame for sending that data over a network. When a device wants to communicate over a network, the NIC takes the packet of data from the device and adds header and footer information to it, creating what is known as a frame.
This header and footer contain important information including source and destination addresses, error checking and other control information. The frame is then sent over the network to reach its destination where it will be de-encapsulated by the receiving NIC which will remove the header and footer, extract the original data packet, and process it accordingly.