Go to:

https://nodered.org/docs/getting-started/raspberrypi

To load node-RED enter the following in Terminal:

bash <(curl -sL https://raw.githubusercontent.com/node-red/linux-installers/master/deb/update-nodejs-and-nodered)

History

Node-RED was invented by J. Paul Morrison in the 1970s, flow-based programming is a way of describing an application’s behavior as a network of black-boxes, or “nodes” as they are called in Node-RED. Each node has a well-defined purpose; it is given some data, it does something with that data and then it passes that data on. The network is responsible for the flow of data between the nodes.  In early 2013  Nick O’Leary and Dave Conway-Jones of IBM’s Emerging Technology Services group picked it up again. What began as a proof-of-concept for visualising and manipulating mappings between MQTT topics, quickly became a much more general tool that could be easily extended in any direction. It was open-sourced in September 2013 and has been developed in the open ever since, culminating in it being one of the founding projects of the JS Foundation in October 2016.