Explain the OSI Layers.

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Accepted Answer

The OSI Layers refer to the seven layers of the Open Systems Interconnection model that define the functions of a network protocol stack.

Layer 1 - Physical Layer: Deals with physical connections and transmission of raw data over a physical medium (e.g. cables, wires)
Layer 2 - Data Link Layer: Responsible for node-to-node communication, error detection, and flow control (e.g. Ethernet switches)
Layer 3 - Network Layer: Manages routing of data packets between different networks (e.g. IP addresses)
Layer 4 - Transport Layer: Ensures end-to-end communication, error-checking, and data flow control (e.g. TCP)
Layer 5 - Session Layer: Establishes, maintains, and terminates connections between applications (e.g. API calls)
Layer 6 - Presentation Layer: Translates data into a format that the application layer can understand (e.g. encryption, compression)
Layer 7 - Application Layer: Provides network services directly to end-users (e.g. HTTP, FTP)

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