system
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human
What is the difference between coke and charcoal?

Thanks for reading. I have tried googling this but it is very confusing and most sources talk about coal vs. coke, not charcoal vs. coke. I understand the superficial differences, coke being derived from the destructive distillation of coal and charcoal being derived from the pyrolysis of wood. I also understand both are essentially high purity carbon.

However the terms are often used differently and in different contexts, and I can't think of what the difference would be (unless they are different allotropes In which case how exactly are they different?). I'm especially interested in when and most importantly why you would use coke for a process instead of charcoal, or vice versa. 

I was looking up how calcium carbide is produced and Wikipedia says it's made with coke, but other sources seem to imply any carbon powder is sufficient, which is where my confusion originated (if that's helpful). Disclaimer: I have zero intention of actually using or making any of these compounds, I know enough lab safety to know I do not know nearly enough lab safety, I am just interested in the theory and the chemistry behind the processes.
gpt
Coke, coal and charcoal are all high carbon fuels that contain other oils and gases.  They have different contaminants, water content and flame temperature.

The main difference you will see is the industrial source.

*Charcoal* is really expensive!  You need to harvest trees, transport them, process them, dry them, etc.  The whole reason the industrial revolution happened is a search for cheap fuel to replace firewood for steam boilers.

*Mineral coal* is really cheap.  Like phenomenally ridiculously cheap.  You have no concept of just how cheap mineral coal actually is for the energy it outputs.  Downside: it's dirty with chemical contaminants and minerals, plus it's also got a lot of water.  The water is a problem because it limits how hot you can make the fire.  Coal burns at about 1000°C.

*Coke* is refined or "cleaned" (not CLEAN) coal.  Someone has removed the water and volatile gases.  All the polluting nasty stuff was burned off elsewhere, so you can now have a clean burning high energy material at the destination.  It burns without smoke.  It also burns much much hotter than coal which allows for useful technologies like making steel, where you need a really hot furnace.  Essentially, coke only produces heat and carbon monoxide gas, which is great at reducing iron  in the steel making process.

Reason you would use coke for calcium carbide is same as making steel.  The reaction is a reduction and you want that clean burning, containment-free coke versus other carbon sources.  Note: We can substitute for mineral graphite in some cases, but historically that has been more expensive than coke.