Plots are numbered automatically when you create them. By default, plot names are based on the plot style name template. You can manually renumber and/or rename them later.
Area plots are numbered automatically in creation order, beginning with the Plot: Next Automatic Area Counter in the Site Properties dialog box. When you renumber plots, numbering begins with the Plot: Next Manual Area Counter. The same concept applies to segment tags.
Tags are the label elements used as key values in plot tables.
When numbering automatically, the increment is always 1. When numbering manually (renumbering), you can select the increment when beginning the renumbering process.