Chronological order is used to organize process essays by discussing the steps of a process in the order they occur. A thesis statement for a process essay indicates the time order of the process and may name the steps. Transition signals are used to show the sequence of steps. The document provides an example outline of a process essay on digestion, with the introduction stating the three major steps of ingestion, digestion, and absorption, and each body paragraph explaining one of the steps in time order.