elements

A regular plural that reaches across every meaning of element: chemical elements, the four elements of the ancient philosophers, and the elements a legal claim must prove. In one meaning the plural is the usual form. Raw material, the substance something is made from, is normally spoken of as elements rather than an element. The plural has also taken on meanings of its own, such as the weather.

Weather pictured as an adversary. In this meaning the word is always plural and nearly always takes the, as in exposed to the elements or out in the elements. A single element never means a gust of wind or a shower. Because it frames weather as something to endure or outwit, it suits writing about sailors, hikers and shelter better than a forecast.

A word for the groundwork of a subject, usually followed by of and the field: the elements of logic, the elements of musical theory. Like the weather meaning, it is plural only. It sounds more formal and more orderly than basics, and it suggests principles laid out in sequence. That is why it suits the title of a textbook.