John, coarse fishing relates to the pursuit of any non salmonid freshwater fish in the UK and Eire. The majority of techniques are oriented around bait for various types. When it comes to Carp it gets very sophisticated with all manner of secret formulas based on dog biscuits, spam, sausage, maggots etc.
Interestingly, coarse fishing has always been predominantly catch and release - most of them taste like boiled newspaper and pins when cooked! When practiced on small lakes, the resident fish get pretty smart once they've been released a few times. Fly fishing is pretty rare, although some people stalk big Carp when cruising just subsurface during the high summer with floating patterns which resemble bread cubes and dog biscuits etc.