“Bootstrapping” comes from the term “pulling yourself up by your own bootstraps.” That much you can get from Wikipedia.
In computing, a bootstrap loader is the first piece of code that runs when a machine starts, and is responsible for loading the rest of the operating system.”
REST is not a specific web service but a design concept (architecture) for managing state information.
First read Ryan Tomayko’s post How I explained REST to my wife; it’s a great starting point. Then read Fielding’s actual dissertation. It’s not that advanced, nor is it long
EDIT: I feel it’s pointless to try to explain REST. It has so many concepts like scalability, visibility (stateless) etc. that the reader needs to grasp, and the best source for understanding those are the actual dissertation. It’s much more than POST/GET etc.