Machine packs are a collection of modularised functions, singularly known as machines. Each machines take inputs, perform one function, and put out an output; any possible error in the function is always accounted for - This is called outcome-orientated programming and is the basis of Sails.js, a realtime MVC framework for Node.JS
Treeline.io is a drag and drop editor for creating powerful backends for apps using the sails.js framework and machines. You can see a list of available machines on the node-machine.org website. With Treeline and the DigitalOcean Machinepack, you can create complex deployment, monitoring and management interfaces without touching any code.
For DigitalOcean, there are several machines in this pack. The create droplet machine, for example, takes several inputs (Size, Name, Location etc), creates a machine, then returns outputs such as the the droplet's IP address, created-at time and more as specified in the machine schema.