Is there actually a difference between basal and bolus?

You could say that basal and bolus is just a description of the insulin's function as opposed to branding any particular insulin as basal or bolus....

I suppose in some way both types of insulin's out there are the same its just that the basal insulin's have an ingredient which slows its action down.....

This explanation is a very basic one as I am sure there are many differences if you look closer..

If you look at the pump then it's the function of the insulin that's relevant here as you're only delivering fast acting insulin - however you have 2 settings for it, so one for bolus and one for basal, the bolus role to manage food/carb intake and basal to keep glucose levels steady over 24 hours.

On multiple daily injections the 2 insulin's are indeed different due to the release rate of basal/bolus in order to perform different roles for managing glucose.

I always think of it as basal being the "base" insulin. It is the background insulin which manages the background "base" glucose your body releases into your blood stream constantly. So the basal insulin needs to be constant. For injections, this is achieved through long acting insulin. For pump, this is achieved by dripping fast acting insulin.

I have yet to find a simple way to describe bolus apart from "not base" or "the other one".
I just looked up "bolus" in the dictionary because I have only ever come across it in terms of diabetes. The dictionary did not help: "a round mass of medicinal material, larger than an ordinary pill." Apparently, it's Latin for "ball". I'm sure it makes sense to someone.

Technically, insulin is insulin, and 1u of "insulin" should change your glucose by the same amount. The key difference, as you mention, is release rate. Basal insulins are constructed in a way that they breakdown and have an impact slowly, whilst mealtime (or bolus) insulins are constructed in a way to minimise protein folding on injection and maintain a monomer structure in order for the body to be able to use them more quickly.

But if you could extract the actual insulin from both and deliver it without the clever protein folding and additives, they should both, unit for unit, have the same effect.

I think the OP is correct. Both basal and bolus do the exact same thing in the body just at different rates of uptake into the cells.