“The internet of things” is a buzzword used more and more. It means that things around you are connected to the (inter)network and therefore can talk to each other and, when combined, offer fantastic new opportunities.
So NodeRed is a NodeJS based toolset that allows you to create so called “flows” (see picture above). Those flows determine what reacts and happens when things happen. Fantastic, told you!
Source 1: http://nodered.org/
Source 2: http://en.wikipedia.org/wiki/Internet_of_ThingsSource 3: http://nodejs.org/