Can you explain me what the difference is between a HALT and a CLOSE?
Mreh, it's all about order status and what you can and cannot do during those times is all.
Here, start at page 8 and read on. (HALT = "Pause")
https://www.cmegroup.com/globex/files/GlobexRefGd.pdf
For the basic trader, this is not important in any way shape or form. "You can't trade futures when it is halted or closed" is all that matters for the majority of us. Easy rule.