When a dog with limited mobility presses a button connected to a Raspberry Pi, Node.js, and Twilio, it sends a text message to the owner's phone via Twilio's API, allowing for communication on a more nuanced level between humans and dogs. The project utilizes a minimal setup consisting of a Raspberry Pi 3, a momentary button, and power supply, with all the necessary code publicly available on GitHub. Trevor Miller built this hack after being inspired by the idea of dogs communicating with humans in a more sophisticated way.