There are many yarns and they are related to many tasks from what we mentioned. Let's look at some applications. First of all, they are widely used in naval operations, in boats - ships - trawlers - and elsewhere. Secondly in agricultural work... tying plants upwards for their growth - grids - fences - tying animals and elsewhere. In medicine… such as dental floss for example or retaining floss in medical aesthetics, sutures and elsewhere. In music… in the strings of musical instruments. Did you forget the clothesline? Or the ropes to the Acrobats?? But let's look at a knot that is easy to hold - not so much for heavy weights…. double metzavolta…