Switch
In plain terms
A device connecting devices within a local network.
Going deeper
A switch forwards data only to the specific device it's destined for within a LAN, using MAC addresses for efficient local delivery. It links devices on the same network.
Under the hood
Operates at layer 2 (some at layer 3), learning MAC-to-port mappings; smarter than a simple hub.
Examples
LANs, connecting computers, data-center networking, VLANs.
Think of it like...
Like an office mailroom delivering each memo straight to the right desk, not every desk.