Spinning is a craft that has many antique words. This is a contemporary description of a spinning mill, that makes perfect sense… to a spinner:

The Carder is the heart of a fiber mill. Each feed of fiber is weighed and placed on the infeed belt. The swift carries the fiber forward. Straightened fibers are carried by the swift to the fancy. The fancy’s card cloth is designed to engage with the swift’s card cloth so that the fibers are lifted to the tips of the swift’s card cloth and carried by the swift to the doffer. The slowly turning doffer removes the fibers from the swift and carries them to the comb where they are stripped from the doffer. A fine web exits the carder.

The web can be turned into batts which are used in quilts and felt making, consolidated into roving, also referred to as sliver, which is further processed into yarns on cones and skeins.
Bumps, skeins, cones, etc may have meant something specific once. But these terms seem to be interchangeable. Added to this is the difference between English as she is spoke in different countries.

One definition of a bump I found on the internet states:
A bump, is a roving that has been carded and is pulled through a tube. It is then slightly twisted into a long continuous fluffy looking thick rope. The roving is then spun onto a cylinder with a center pull. The finished bump looks similar to a large cone of yarn. The roving is then pulled out of the bump from the center or the roving can be unraveled from the outside. This product is great for handspinners. This bump gives the handspinner control of the roving and helps to prevent the roving from becoming difficult to store. But the term bump is also used to refer to thicker core spun yarn, eg for rugs, often of alpaca.
An Australian shopping in a US yarn store would confuse the owner. She would call a US skein, a ball of yarn. And the US hank would be called a skein. We are used to buying balls of yarn wound into elongated spheres that can be unwound from the center or the outside. They think of balls only as spheres with one end hidden in the middle.
Skein rhymes with cane most of the time but I have heard it pronounced in US like scene with a hard c). Its alternate meaning is: A flock of geese or similar birds in flight.
So some US, local yarn stores offer a winding service to convert hanks (ie skeins) of yarn by using a yarn (or ball) winder and a swift into an easy-to-use cake of yarn, a cylinder with a flat top and bottom, that sits flat while you knit it. We would call that cake a ball too.
Or you could wind the yarn onto a nøstepinde (also spelled as nystepinne or nostepinne depending on which of the Scandinavian languages is used.) This is usually a wooden stick with one end tapered, so that the ball slides off easily.
In the old days, yarns were wound into hanks (or skeins) of a specific length. (For wool, yarn in hanks was 560 yards long. Cotton hanks had 840 yards or 7 leas of yarn.) The number of hanks that weighed one pound gave an indication of the diameter of the yarn. There would be fewer hanks per pound of thicker, heavier yarns than of thin, light yarns. Hence, the lower the number, the thicker the yarn using this Worsted count (or spinning count.) Knitting wool still quotes the yards per unit (ball, skein or hank) and knitting patterns from the US stipulate number of yards that needed to make the item. Australian patterns quote the number of balls needed for a project.
A cone of yarn has yarn wrapped around a conical cylinder typically made of heavy cardboard or plastic. Yarn is usually only sold in cones when it’s a large quantity. For example, in weaving, it’s important to have a long length of yarn (without knots, so cones are sold with these long lengths of yarn.
Cheeses have a generally cylindrical outer configuration, eg a cylindrical, truncated conical, pineapple cone form, etc.
A cop has yarn wound onto a solid base eg a spindle shank. Cops for industry are wound with a semicircular base, cylindrical body and conical top. Most of the thread is wound close to parallel from bottom to top. The path of the yarn back to the bottom of the base is more open and diagonal. This difference in packing density prevents the layers from sloughing off together.
Yarns can also be wound on bobbins, pirns, tubes or spools. A spool is usually a low-flanged or unflanged cylinder ie it has a rim or ridge at each end and a hole through the middle, on which thread, wire, cable, paper, film, straps, or tape is wound for distribution or use. Whatever is the difference between a spool and a reel of sewing thread?
Are you confused yet?
According to glossary of The Textile Arts, by Verla Birrell, published in 1973:

Bobbin: A small stick, card, special quill or tube on which thread is wound. There are various kinds of bobbins: stick, tube, argyle (used in knitting: a small opening for the thread prevents the bobbin from unwinding), lace, match case, etc
Cop: A paper tube bobbin on which thread is wound
Plait: A braid or mat of vegetable fibres
Reel: A swivel type of warping board. May also hold yarn as it is being spun.
Spool Board: A horizontal board with spikes projecting upwards; usually holds 30 spools or bobbins
Dog: Catch that holds rachet wheel