This document discusses prototyping and provides guidance on how to prototype effectively. It states that prototyping is the iterative generation of artifacts to answer questions and test hypotheses. Prototyping allows you to gain empathy, explore ideas, test solutions, and inspire others. The document recommends prototyping early and often to fail cheaply, identify key variables to test, and use different resolution levels of prototypes over multiple iterations. It also suggests prototyping intangibles like digital products and services, as well as using analogous situations when the actual context is inaccessible.