im confused about the purpouse of MQTT,

[steel bison]

Because MQTT is low overhead - even a tiny ESP can handle that

MQTT is a standard - lots of things know how to communicate over it

HA is not a standard 😉

[brisk ember]

yes, but when using HA why not just use HA alone? im trying to learn

[steel bison]

https://en.wikipedia.org/wiki/MQTT

Because lots of devices already speak MQTT

And libraries exist for it

[brisk ember]

therefore it makes it easier to intrergate ith HA?

with

[steel bison]

If you want to use an ESP and have it talk MQTT that's trivial

The same for HA isn't necessarily the case, unless you use ESPHome

Also, the overhead for HA's API is probably larger than that of MQTT

Think of MQTT as the closest thing to a "universal language" as you get for IoT

[brisk ember]

i understand.