[shaunpersad]

I personally have found the following blog posts extremely helpful in learning about MQTT: https://www.hivemq.com/tags/mqtt-essentials/

Also, the spec is actually pretty readable: http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-o...

Note: I'm not affiliated with HiveMQ.

[thunderbong]

That's a really good series of blog posts. Thanks.