This chapter is devoted to the "verbs" in the interface. We've spent a lot of pages talking about overall structure and flow, visual layout, and "nouns" such as windows, text, links, and static elements in pages. Chapter 6 spends even more pages on nouns, and Chapter 7 handles traditional (and a few nontraditional) controls and widgets: things that let users supply information and set state, but that don't actually do much.
So now let's talk about buttons and menus.
Sounds exciting, doesn't it? Probably not. Desktop interfaces have been using menu bars as long ago as the first Macintosh, and buttons for even longer. What we think of as "buttons" are only a visual rendering of a physical device that predated GUIs anyway.
It's true that there is a lot of history here, and many best practices to follow. The standard platform style guides, such as Windows, Macintosh, and PalmOS, generally get you pretty close to a workable UI. Most users depend upon learned conventions to negotiate menus and find buttons, so it behooves you to follow those conventions, even when they feel restrictive or nonsensical.
Common functionality like cut, copy, and paste also carries lots of historical baggage—if it could be reinvented now, it probably would work differently, but even moderately experienced desktop computer users have learned how it's "supposed to work." The same is true for pop-up menus (context menus), which some users seem to look for everywhere, and ...