"DIR" is used to list a subdirectories, files or file in the location you are in on your computer.
"DIR" when used on its own will list all files and directories that you are in
"DIR /P /W" will list all files and subdirectories from your location on your computer, but will also list them in several rows and pause every page.
"DIR /AH" will show all hidden files and directories in present location.
"DIR /AD" will show all directories in present location.
"DIR /?" will give you further help when using the command.