I didn't know this so I am sharing it
Windows OS
if you are in a directory using CMD and want to open explorer from that same place type in "Start ." no quotes of course and explorer will open in that directory
Mac OS X
if you are in terminal and want to open finder in that directory just type in "open ." and you will have finder open.
Linux (I use CentOS7)
just create an alias with this command alias open='xdc-open &> /dev/null'
I hope you can profit from this
