dir *.txt *.doc		# filter by extension (both doc and txt)
dir	/a:-d			# files only (no subfolders)
dir /s				# current directory and subfolders content
dir /s /a:-d		# files only (including subfolders)
dir > myfile.txt	# stored in myfile.txt (dir /s > myfile.txt with subfolders)
dir /o:[sortorder] 	# example:  dir /o:-s    (sort by decreasing size)
  N : By name (alphabetic).
  S : By size (smallest first).
  E : By extension (alphabetic).
  D : By date/time (oldest first).
  - : Prefix to reverse order.