Thanks, SkiperJohn I appreciate your answer. I've indeed come to those questions in the course of reading about catamarans. - That 'composite' relates to the mixture of material used is entirely reasonable. In consequence, I'll drop my notion that it refers to adding and substracting parts
of a pole, making it longer or smaller.
Well, once more, I cannot help the appearance of trolling.
Perhaps the questions are ridiculous. Granted. But even then they are wholly serious. - Well, I hope someone will help me sort trough with this. As I pointed out, there are still terms left I cannot make out and will post very soon.
Thanks again, Talbot, for your efforts. I'm sorry if my thanks have been expressed too enthusiastically and thus were responsible for creating the impression of trolling. - But enough of this. I think it's a poor sign of the degree of hospitality in a forum if anyone 'from the outside', lacking proper knowledge of the material discussed there and suitability of choice of vocabulary, stumbles into a general suspicious atmosphere, trolls being smelled everywhere.