MQTT (Message Queuing Telemetry Transport) is a lightweight messaging protocol designed for IoT (Internet of Things) applications. It operates on a publish/subscribe model, making it ideal for environments with limited bandwidth or unreliable networks.

How does it work? In the MQTT model, there are clients (devices or applications) and a broker (server). Clients can publish messages to specific "topics" or subscribe to receive messages on particular "topics." The broker is responsible for distributing messages from publishers to their respective subscribers. This design minimizes overhead and enables efficient communication among a vast number of devices, ranging from simple sensors to complex cloud platforms.

MQTT is widely adopted in IoT solutions because it facilitates reliable and efficient communication between millions of devices, even under challenging network conditions.