Raku allows for several different programming paradigms; procedural, functional, (as in languages like LISP), and object-oriented. It is possible to write purely procedural Raku, while ignoring O-O features completely, though it does take some dodging.
Object-oriented.programming first surfaced in the mid 1960s in research projects, but was more generally visible by 1980. Like all new programming concepts, it was going to cure cancer, bring about world peace, and produce bug-free software. (And didn't, of course.) It naturally had its specialised jargon, designed to ensure tribal solidarity and repel infidels. It gradually spread with languages like C++, (1979-83), but remained a niche concept until Sun introduced Java in 1995. https://www.indeed.com/career-advice/career-development/what-is-object-oriented-programming With the success of Java, later Javascript, and other new languages, O-O and its jargon became sufficiently mainstream that even many programmers working with other languages learned the terminology. I suspect that many programmers trained since the mid-90s assume that it's the only way to code, and that objects and classes are inherent parts of everyone's universes. If you were discussing the assembly language for bicycles, any documentation could reasonably assume an understanding of frames, wheels, pedals, and bell-cranks. Equally, any discussion of object-oriented features can reasonably assume an understanding of generic concepts like objects, classes, and inheritance, provided it points out local weirdnesses. Repeating all the basics would make the text cumbersome. Perhaps the best approach would be a hyperlink to a generic description (of which there are probably thousands already on the Web) the first time a terms is introduced. The naive could follow it to enligtenment, while the cognoscenti would not be distracted by it.