With the confusing terminology in this thread I did some research in catalogs. I am more confused as different manufacturers use different names for the same items. I go back to my industrial construction career and basically we used three devices: grab hooks used with chain only, designed to hook over a chain link to make a loop or shorten (never hook something on the point as it opens up the hook); slip or hoisting hooks that have an open hook for attaching to a fixed device or making a sliding loop that tightens itself, not to used in the eye of a cable or strap; shackles are a steel U shaped device with a bolt that closes the loop, used to provide an attachment point at a hole or eye, to hook up several lifting/dragging lines/straps at one point, and to provide a sliding loop in cable or straps. The eyes and run of cables and slings are never used w/o a shackle. There are many local terms that you have to sort out on your own as they are numerous. Loggers and sailors have their own unique language for example. We could make this go on awhile getting posts for all the variations out there.
Ron