The mosquitto broker package ships commandline tools (often as *-clients package) to send and receive MQTT messages. As an alternative have a look at hbmqtt_pub and hbmqtt_sub which are provided by HBMQTT. For sending test messages to a broker running on localhost check the example below:

mosquitto_pub -h 127.0.0.1 -t home-assistant/switch/1/on -m "Switch is ON"

Another way to send MQTT messages manually is to use the “MQTT” Integration in the frontend. Choose the “Configuration” tab, click “Integrations” and click the “Configure” option under the “MQTT” integration. Enter something similar to the example below into the “topic” field under “Publish a packet*.

home-assistant/switch/1/power

and in the Payload field

ON

In the “Listen to a topic” field, type # to see everything, or “home-assistant/switch/#” to just follow the published topic. Press “Start Listening” and then press “Publish”. The result should appear similar to the text below

Message 23 received on home-assistant/switch/1/power/stat/POWER at 12:16 PM:
ON
QoS: 0 - Retain: false
Message 22 received on home-assistant/switch/1/power/stat/RESULT at 12:16 PM:
{
    "POWER": "ON"
}
QoS: 0 - Retain: false

For reading all messages sent on the topic home-assistant to a broker running on localhost:

mosquitto_sub -h 127.0.0.1 -v -t "home-assistant/#"

Source: MQTT Testing – Home Assistant

Installation

This integration is available in HACS (Home Assistant Community Store)

1. Using the tool of choice open the directory (folder) for your HA configuration (where you find configuration.yaml).
2. If you do not have a custom_components directory (folder) there, you need to create it.
3. In the custom_components directory (folder) create a new folder called nodered.
4. Download all the files from the custom_components/nodered/ directory (folder) in this repository.
5. Place the files you downloaded in the new directory (folder) you created.
6. Restart Home Assistant
7. Refresh your browser window (bug in HA where it doesn’t update the integration list after a reboot)
8. In the HA UI go to “Configuration” -> “Integrations” click “+” and search for “Node-RED Companion”

Using your HA configuration directory (folder) as a starting point you should now also have this:

custom_components/nodered/translations/en.json
custom_components/nodered/__init__.py
custom_components/nodered/binary_sensor.py
custom_components/nodered/config_flow.py
custom_components/nodered/const.py
custom_components/nodered/discovery.py
custom_components/nodered/manifest.json
custom_components/nodered/sensor.py
custom_components/nodered/services.yaml
custom_components/nodered/switch.py
custom_components/nodered/websocket.py

Source: GitHub – zachowj/hass-node-red: Companion Component for node-red-contrib-home-assistant-websocket to help integrate Node-RED with Home Assistant Core

Home Assistant Operating System (HassOS) is based on buildroot. It’s a hypervisor for Docker and supports various kind of hardware.

Source: Home Assistant OS – Google Search

Thomas Joseph Kelly (June 14, 1929 – March 23, 2002) was an American aerospace engineer. Kelly primarily worked on the Apollo Lunar Module, which earned him the name of “Father of the Lunar Module” from NASA.

Kelly graduated from Cornell University in 1951, where he was a member of the Quill and Daggersociety. Afterwards, Kelly obtained his MS degree from Columbia University and Ph.D. from the Polytechnic Institute of Brooklyn.

Kelly was the project engineer, engineering manager and deputy program manager for Grumman Aircraft‘s Apollo Lunar Module (1962–1970). His 2001 book Moon Lander: How We Developed the Apollo Lunar Module documents the process of designing, building and flying the Lunar Module.

Kelly was portrayed by Matt Craven in the 1998 miniseries From the Earth to the Moon.

https://en.wikipedia.org/wiki/Thomas_J._Kelly_(aerospace_engineer)

Syntax

https://www.arduino.cc/reference/en/language/structure/further-syntax/include/

https://www.aliexpress.com/item/32879426956.html?spm=a2g0o.search0302.0.0.51e47a83FZWg62&algo_pvid=null&algo_expid=null&btsid=0bb0622916203915583268269e177d&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

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