This wooden fid is a long, tapered tool used for opening strands in line for splicing. Never use it for anything else, and never hammer the butt end of a fid to drive it through. It splits or splinters rope very easily. To open heavy line, set the butt of the fid on deck and hammer the line onto the point. Never call a fid a marlin spike.
A variety of styles and sizes. These needles are primarily used to mend and construct nets for the fishing industry.
A tapered steel tool, serves the same purpose with wire that the fid does with line. A good spike should never be used as a crowbar or a pin to open shackles and care must be taken to avoid bending or blunting its point. Unlike the fid, you can hammer the butt of a marlin spike.